Matching 14kt Gold Mokume Gane Wedding Rings

In this instructable, I will show you how to make matching wedding rings out of 14kt gold mokume gane (pronounced mow-koo-may gah-nay, which means wood-grained metal).  While it may seem like a complex technique, I assure you anyone can make these with the right knowledge, the right tools, and enough patience.  The first two are easily acquired, the last one takes time.

Mokume gane is a technique that joins dissimilar metals together for ornamental purposes.  Metals are joined by diffusion bonding to create striking contrast and patterns.  There are hundreds of different metal combinations, patterns and techniques to choose from.  I chose a textured combination of 14kt red, yellow and white gold.  Because all these metals are relatively inert, it provides a comparatively easy example.

I have no formal or informal training in jewelry or silversmithing.  However, I have done some blacksmithing, and I study materials science.  Don't let that scare you!  I will explain the theory behind each step, how to do it, and what to do if things go wrong.  You don't need any previous experience to get this right.

This instructable is based loosely on the website I made to catalog how I made the wedding rings.  The wedding site reads more like a story than an instructable, which is why I've restructured it for you.  You can find the original here:  http://www.mike-short.com/MnM/Rings/Rings-Intro.shtml

Step 1: Overview and Materials List

The goal of this project is to make matching mokume wedding rings from scratch.  This is accomplished in four major parts:

1)   Make a billet of mokume gane from starting metals.
2)   Cut, roll and shape that billet into strips for making rings.
3)   Form these blanks into rings, solder them together and size the rings.
4)   File, shape and polish the rings to a mirror finish.

There are many intermediate steps inside each major part.

Here is a list of tools and materials, along with links to buy them and prices as of February, 2011.  I've split the materials into the four major parts. The entire project takes a couple weeks to finish, and each of the four parts can be done on its own with a long break in between.  The materials list is a bit long, but having the right tools for the job makes it go far more smoothly.  The total cost for the project with prices from Feb. 2011 is $2,168.30.  Of that total, $1,719.00 is the gold metal, while the remaining $449.30 gets you all the tools, supplies and safety equipment to finish the entire project.  Finding or borrowing tools and supplies substantially lowers this cost.
*Note: You can substantially lower the cost of this project by using different metals, such as silver, copper or brass.

Safety Supplies (Safety First!!!) (Total cost - $36.51)
(1) Safety glasses with side protection
      http://www.riogrande.com , P/N 201708, $8.20
(5) Pairs of nitrile (blue or purple) gloves
      http://www.vwr.com , P/N 414004-441, $12.62
(1) Lab coat or other long sleeve expendable clothing
      $0, just use an old long sleeve shirt
(1) Plastic face shield
      http://www.mcmaster.com , P/N 5481T28 , $15.69

Part 1 - Starting Metals (Total cost - $1,719.00)
*Note:  The prices of gold change by the day.  Check a reputable metals site, such as http://www.kitco.com for current prices.
(2) 1" by 1" sheets of 14kt white gold
      $348 (Feb. 2011) x 2 = $696.00
(2) 1" by 1" sheets of 14kt yellow gold
      $348 (Feb. 2011) x 2 = $696.00
(2) 1" by 1" sheets of 14kt red gold
      $348 (Feb. 2011) x 2 = $696.00
Recovered dust & scraps
      (-$369.00, adjusted to Feb. 2011 prices)

Part 1 - Supplies for Mokume Billet Making (Total cost - $158.65)
(1) Senpak heat treatment bag, 8" x 10"
      http://www.mcmaster.com/ , P/N 3438K14, $9.35
(2) Pounds of dry WOOD charcoal, not briquettes!
      http://www.acehardware.com or local hardware store, P/N 8231144, $7.49
(1) Small container of acetone
      Local hardware store, ~$10.00
(2) Steel plates, 4" x 4" x 1/2" thick
      http://www.mcmaster.com , P/N 6554K321, $34.32 for a 4" x 12" x 1/2" piece
(4) 5/16" to 7/16" hex head bolts, 2" to 3" long
      http://www.mcmaster.com , P/N 91247A320, $10.03 for a 25-pack
(4) Matching nuts for the bolts above
      http://www.mcmaster.com , P/N 95505A614, $8.66 for a 100-pack
(8) Matching washers for the bolts above
      Local hardware store, ~$1
(1) Bottle of White-Out or Liquid Paper
      Local office supply store, ~$2
(1) Piece of firebrick or insulating material to use as a heat-resistant surface
      http://www.mcmaster.com , P/N 9355K2, $8.62
(1) Propane torch (not MAPP gas)
      Local hardware store, ~$25
(1) Pair of tongs, strong metal tweezers, needle nose pliers or other tool for picking up hot metal
      http://www.mcmaster.com , P/N 7379A24, $7.18
(1) Bucket of water for quenching (fast cooling)
      Found $0.00
(2) Wrenches for tightening nuts & bolts above (I like adjustable wrenches)
      Local hardware store ~$30
(1) 1/2" drill bit
      Local hardware store, ~$5
(1) Glass or pyrex container, with a capacity of 100mL to 250mL
      Found, ~$0

Part 1 - Access to Big Machines for Mokume Billet Making
-Furnace (must be set to 100°F (~55°C) lower than the lowest melting point among your metals)
-Vise
-Drill Press
-Bandsaw

Part 2 - Supplies for Making Ring Blanks (Total cost - $87.70)
(1) Piece of 180-320 grit sandpaper
       Local hardware store, ~$2
(1) Piece of ~600 grit sandpaper
       Local hardware store, ~$2
(1) Jeweler's saw
      http://www.riogrande.com , P/N 110131, $11.00
(12) #2 jeweler's saw blades
      http://www.riogrande.com , P/N 110101, $17.50 for a pack of 144
(1) Stick of jeweler's saw lubricating wax
      http://www.riogrande.com , P/N 117003, $5.25
(2) 1" x 1" pieces of sturdy cardboard
      Found, $0.00
(1) Pair of calipers or very precise ruler
      http://www.riogrande.com , P/N 115189, $27.00
(1) Metal hammer (see below) or rolling mill
      http://www.riogrande.com , P/N 112530, $22.95

Part 2 - Big Machines for Making Ring Blanks
-Vise
-Rolling mill (optional), hand-cranked or powered

Part 3 - Soldering and Sizing the Rings (Total cost - $162.44)
(1) Box of Rio-Pickle pickling agent for non-ferrous metals
      http://www.riogrande.com , P/N 5010233, $11.25 for 3 lbs.
(1) 16 oz. mini Crock Pot
      http://www.riogrande.com , P/N 501012, $19.25
(1) Thermometer (just has to go to 212°F (100°C))
      http://www.mcmaster.com , P/N 6182K14, $13.96
(1) Box of baking soda
      Supermarket, ~$3
(1) Glass stirring rod
      http://www.mcmaster.com , P/N 8496K12, $1.77
(1) Bottle of gold & silver liquid flux, 1 pint
      http://www.riogrande.com , P/N 504006, $8.95
(6) Inches of MEDIUM grade, 1/16" 14kt yellow gold wire solder
      http://www.riogrande.com , P/N 600857, $20.76 (as of Feb. 2011)
(1) Propane torch
      Use the one from Step 1, $0.00
(1) Bucket of water for quenching
      Use the one from Step 1, $0.00
(1) Mandrel with ring sizes
      http://www.riogrande.com , P/N 112367, $26.50
(1) Plastic or neoprene hammer
      http://www.riogrande.com , P/N 112800, $47.00
(1) Metal cross-peen hammer
      Use the one from Step 2, $0.00
(1) Medium size hand file
      Local hardware store, ~$10
(1) Kitchen measuring cup
      Your kitchen, $0.00

Part 3 - Big Machines for Soldering and Sizing the Rings
-Vie
-Somewhere with ventilation

Part 4 - Finishing and Polishing the Rings (Total cost - $4.00)
(1) Medium size hand file
      Use the one from Step 3, $0.00
(1) Small needle file
      Found, $0
(1) Propane torch
      Use the one from Step 1, $0.00
(1) Bucket of water for quenching
      Use the one from Step 1, $0.00
(1) Mandrel with ring sizes
      Use the one from Step 3, $0.00
(1) Plastic hammer
      Use the one from Step 3, $0.00
(1) Metal cross-peen hammer
      Use the one from Step 2, $0.00
(1) Piece of 180-320 grit sandpaper
      Use the one from Step 1, $0.00
(1) Piece of ~600 grit sandpaper
      Use the one from Step 1, $0.00
(1) Piece of ~1200 grit sandpaper
      Local hardware store, ~$2
(1) Piece of ~2400 grit sandpaper OR rag and stick of rouge
      Local hardware store, ~$2

Part 4 - Finishing and Polishing the Rings
-Vise
-Lathe (optional, but saves a LOT of polishing time)

Comments

[kyle.marsh]

Whew...this is slow work without a rolling mill. At least in copper and brass. I don't seem to be able to reduce the thickness by quite 25% before the piece pretty much stops flattening and I need to anneal it again (I presume it work-hardens slightly faster than gold, then? Or maybe it's just that the copper is generally more of a pain to work with than gold).

Question on the measurements, though...I started with a billet approximately 1"x1"x0.24" (six 1" squares of 18ga metal) and after reducing its thickness to about 0.17" I haven't really extended the billet very much...my planning calculations indicated that I should have a blank that's about 2.3" long but it's still only about 1.2". Am I on the right track, or did I miss something?

Also, you say to repeat the process of reducing thickness and extending length until the billet reaches the dimensions from the planning step...is that correct? should I get the billet to be the final size in this step before increasing the layers? Once I increase the layers the billet will double in thickness and halve in width, won't it?

Oh, and I guess I should ask if I'm supposed to be making the billet both wider and longer in this step, or just longer? I've been hammering along one axis only so far and that's made the billet slightly longer but yet much wider.

Thanks again. I'm really having fun with this project.

[hereiam]

Hi Kyle,

I think you're on the right track. Copper is indeed tougher to work with than gold, since it work hardens faster and therefore will crack more easily. Gold is totally the best!

And as for the billet sizes, keep in mind the assumption of constant volume for your billet. If it's 1x1x0.24, then you've got 0.24 cubic inches of material. If you reduce the thickness to 0.17", you still have the same volume of material. If you assume all the length extension goes into one dimension, then you would have a billet that's 0.24"/0.17" = 1.41" long and 1" thick. In reality you get some expansion in both dimensions, so if you assume your billet has become 1.1" wide, and it's 0.17" thick, then it would be about 1.28" long. I hope that makes more sense in terms of conserving constant volume.

The reason I say to get the billet down to final dimensions before halving is that it's easier to deal with a thinner billet than a thicker one. If you halve the billet and start rolling it, you'll have to go through more steps and more hammering than if it's thinner.

Finally, as to making the billet wider/longer, that depends on the ring blanks that you want to cut out. I don't think it matters too much at this stage, especially if you just have flat layers. If you already have patterns then you have to think about how you want them to deform.

Keep the questions coming, I'm more than happy to help out!

Cheers,
-Mike

[kyle.marsh]

I've been having a lot of trouble with my second practice billet delaminating as I'm hammering it out. I think it's because my compression jig has been failing, but if that doesn't solve it I may try to find a rolling mill. I looked through Rio Grande's catalog and all the ones they have say "maximum sheet thickness" is 4-6mm depending on which one you get...is that going to be sufficient, or do I need to try to find one with more clearance?

[kyle.marsh]

I just realized why I've been having so much trouble with delamination on my second practice run: I had someone make my compression jig out of 4 sheets of 1/4" steel instead of 2 sheets of 1/2" (and he did a crummy job of aligning the holes, which creates more issues). The doubled sheets can slide across one another and warp separately, so after two firings the whole thing curved in enough to be almost useless -- the edges would touch and the center would still have a little "bubble" of space in there. Looks like I'll have to actually find a shop where I can cut and drill half-inch steel plate.

[kyle.marsh]

Practice round 1 is done! These rings are copper, brass, and nickle. I learned a bunch of stuff from this that I'll try to apply to round 2:

• Use a file, not sandpaper to clean up edges after baking/cutting billet
• Use cross-peened end of hammer to extend billet, but use broad face and gentler strikes as you get close to the desired thickness to minimize metal loss when grinding billet smooth
• Form the blank around the mandrel then place it in the vise to get the edges aligned well for soldering
• Use a thicker ring blank to give more leeway for shaping the ring so it's not so flat

I'll post more things that I discover as I come across them.

[hereiam]

This looks great, Kyle! Congrats on your first mokume project! I agree, it's good to start thicker, that way you have the freedom to file a comfort fit should you so choose. Did you twist your billet, or did you apply a diagonal texture with a hammer like I did?

[kyle.marsh]

I did not twist the billet, although that's an intriguing thought.... No, I actually used a dremel to cut diagonal slashes through a couple layers after the final diffusion bond and then hammered that out to get the billet to the final dimensions for the blanks. However, since I'm using the hammer to extend the billet rather a rolling mill I probably got a lot of texturing done while extending the billet.

Speaking of the rolling mill, actually, a friend whom I'm keeping abreast of my progress keeps pressing me to try to find a rolling mill that I can access because it will save much time and grief (which is probably true). Another friend who was an apprentice jeweler mentioned that this kind of application might damage a rolling mill, though, and I'm curious if you had any light to shed on that possibility.

[hereiam]

I don't think that rolling mokume of any soft metal will damage a rolling mill at all, or at least one of considerable size. My rolling mill has 4" diameter rolls, which is quite large compared to hand cranked ones, but small compared to giant industrial rolls. I used my rolling mill just for extension of the billets in an already-flat state, not for any funny shaped things.

I agree with your hammering the texture after dremeling, since that gives you finer spatial control over deformation at every location on the ring. Rolling that could lead to uneven thicknesses, or even side-to-side warping.

[kyle.marsh]

That's what I was guessing. Now I to see if I can find one that I can use...hrm. Anyway, I'll keep you posted on my progress. Thanks again for all your help!

[kyle.marsh]

Okay, so are these dimensions (in step 3) the size of the *billet* after all the layer increasing and cold working is done, or of one of the ring blanks that you cut from the final billet? Because your instructions have us make the ring slightly small and then stretch it on the mandrel, I'd expect the length of the blank to be shorter than the circumference of the finished ring and the other two dimensions to be slightly larger, but here you've got all three a bit larger. Am I missing something?

[hereiam]

Actually, since you end up grinding a 45 degree bevel into the billet, the billet length exceeds the ID circumference, but removing the length of the bevel will usually decrease that. Plus the act of bending it in a circle puts the ID in compression, further reducing the inner circumference. If the ring were infinitely thin, then bending it wouldn't change its length. However, for billets with real thickness, the outside stretches (tension) while the inside gets compressed. I hope that helps, please let me know if it doesn't make sense, and good luck!

[Karylmatt]

After using the gold metal detector I found that it is really a good device, it can not only help to save time but also can help you to save energy. And besides being used for looking for gold, the gold metal detectors can alao be used to help the archologist in finding treasures and used in many other important places as security tool.

[kyle.marsh]

Got it, thanks! I didn't realize the compression would actually change the length of the billet significantly. Makes sense, though.

[kyle.marsh]

Hey, it's been a while and I'm not sure if my last question got lost in your inbox (or never made it) or if I've just worn out my welcome with the questions :-)

I'm curious what gauge sheet metals you recommend starting with and also how much I need to worry about elements that only show up in small amounts in my metals forming eutectic alloys that I need to worry about.

Thanks!

[hereiam]

Hi Kyle,

Sorry I didn't get a chance to respond to you earlier! I started with 18 gauge sheets of gold, and I wouldn't worry about very minor elements. They won't change temperatures that much in most cases. If you stay 50-100F below the melting point then you've got a bit of margin, while you'll still form a nice diffusion bond.

Also, if you run the bond for a while and it doesn't take, you can always keep cooking it for longer (provided your metals are cheap), and try different combinations of time and temperature.

You can certainly start with thicker metal; just keep in mind that you'll have more rolling to do. You'll also cut through fewer layers for the same depth of cut. It's all about how bold/fine you want your patterns to be in the end, and at what stage you apply deformation(s).

Finally, bonding for a long time will cause your lines to become a bit blurry and diffuse. You may be going for this, though a lot of what makes mokume look nice is just how crisp the lines are. I usually go for the minimum necessary to ensure a good bond, so my lines stay nice and sharp.

Also, check out the next set of wedding rings I just finished:

http://www.mike-short.com/Art/2012_08_02_JoseJaneRings/

These were one-hour bonds using 80/20 silver and 14kt white gold. I had 10 sheets of each, using 14ga. silver and 18ga. gold to even out the weight percentages. Much of the patterning was done after significant rolling, so more layers would be cut through. This one had hemispherical pits drilled using a ball end mill, to get the 'knots in wood' effect.

Cheers,
-Mike

[kyle.marsh]

Those are beautiful, Mike! Good to know that I don't have to worry too much about elements with very small percentages, but I'm also curious about the Cu-Zn system. Looking at the binary phase diagram I see that the melting point of copper-zinc alloys monotonically decreases as the percentage of zinc gets higher until you get pure zinc. I'm thinking of doing some trial runs with copper and brass, and the brass looks to be up to 41% zinc (and the rest mostly copper).

Can I run my bond at a temperature 50-100°F cooler than the melting point of a 41%-Zinc alloy, or do I have to worry about higher concentrations of zinc forming or something?

As for diffuse vs. sharp bonds...I shall have to experiment to see what I like. A lot of mokume is a bit too bold for my tastes; one of the reasons I really like your wedding bands is the subtlety of the pattern. I'll have to play around with it a bit.

Thanks for the help!

~Kyle Marsh

[kyle.marsh]

I'm working on doing this for my own wedding and just starting to get my equipment.  I've got three questions so far:

1. I'm considering buying a glass fusing kiln to use as the furnace.  I see that 14k golds have melting points somewhere around 1800°F, and a full fuse for glass operates around 1700°F, so I think that a kiln capable of 1800-2000°F should work; am I correct in my thinking, or is there something else that I need to consider?
2. You mention that the torch used for annealing and soldering should be propane, not MAPP gas...why is this important? Is it temperature, or will MAPP react poorly with something?  I picked up a dual MAPP/Oxygen torch for cutting, brazing and welding figuring that it'd work, but if not I can return it and find something else.
3. For practicing with less expensive metals I expect the metals to have substantially different melting points; I'm guessing that I need to do my diffusion bond at 100°F cooler than the lowest melting point of the mix? should I make time adjustments to account for this?

Thanks! This is a fantastic instructable and a great project.

[hereiam]

Hi Kyle,

Thanks for the compliments, and the good questions! To answer them in order:

1) I think your kiln will work OK, as long as you can control the temperature to within about 25F. You want to keep the temperature about 50-100F below the lowest melting point alloy that will be formed. To find this you need to look at "binary phase diagrams" for each combination of elements in your golds (just Google these). Check or ask for the compositions of your 14kt golds; not all are the same. Sometimes you can't just go with the lowest melting point metal, because a lowe-melting-point "eutectic alloy" can form. If you need help interpreting these binary alloy phase diagrams, just ask.

2) The reason I suggest using propane instead of MAPP is because the flame is cooler (relatively), which gives you more control over the heat throughout the billet. MAPP can cause the outside to start to melt, which looks like the billet is "sweating." This means that you'll have no layers where melting occurs, and you'll partially ruin your pattern. You'll have to heat for longer with propane, but the billet will heat more evenly.

3) Again, see #1 for an explanation on picking the right temperature. I have used silver and gold together, which have very different melting points. I picked a temperature about 75F lower than the temperature of the eutectic alloy formed between gold and silver.

Good luck to you! I'm working on another set of billets, and I"ll be sure to post pictures soon.

[kyle.marsh]

Okay, I've got most of my equipment and I'm looking at metals now. I'm using brass, nickel and copper for my practice run and I've been able to find binary phase diagrams for most of the common elements (copper, zinc, and nickel) but my metals also have trace amounts (< 6%) of lead and manganese and I'm having a harder time finding diagrams for those elements; do you know where I might find those?

I've also got a question about what parts of the diagrams I have to worry about are. For instance, looking at the Cu-Zn diagram, the lowest melting point is pure zinc down around 775°F, but my metals have at most 60% Zinc (where the melting point is all the way up at 1500°F). Do I only have to worry about the highest concentration of each element within my metals, or do I have to take the entire range of concentrations into account for every elemental combination? What about those trace elements?

Finally, what gauge of metal do you use to make your billets? Should the overall stack of metal be approximately the same thickness that you want the ring to have? 25% thicker? Twice as thick? I know there's a step to roll or hammer it out to the right thickness, but what's a ballpark number to shoot for?

Oh, and regarding patterns...I haven't looked this up yet, but I'm guessing the longer you let the diffusion bond go for, the more gentle your final pattern will end up being? As in, a short bond would keep the layers pretty distinct and I'd get sharp contrast in the final pattern, but a longer bond would let the layers blend into one another more gradually resulting in a more subtle appearance. Am I on track with that, or am I chasing a red herring?

Thanks!

[kyle.marsh]

Okay, good to know! I just discovered that I can get an MSDS from Rio Grande for their gold. So I need to look up the binary alloy phase diagram for every pairing of elements in there...that's simpler than it might have been! I'll ask you if I need help figuring it out.

I figured that heat might have been the issue with a MAPP torch. And mine has a nice fine tip for cutting, too. I'll go back and get a propane torch instead; sounds like less to worry about overall.

Thanks for the advice! I'll make sure to share thoughts and pictures as I progress!

[kyle.marsh]

Hmm...Actually I have another question. After step 15 you repeat the diffusion bond process with the two (or more) sections of the billet that you currently have. But in step 13 if you use a hammer to extend the billet rather than a cold roller I could imagine the surface being uneven...sort of "rippled", I guess.

If you have a rippled surface I imagine you'll need to find some way of making the faces you're mating perfectly flat before setting up for another diffusion bond? Is that taken care of in the grinding after you extend the billet?

[hereiam]

Hi Kyle,

You can certainly use a hammer, imparting a rippled texture to the layers. You will have to ensure near-perfect smoothness between layers before rebonding, which I would do by grinding/polishing your billet flat after hammering. I actually used a hammer to impart some texture after the ring was formed, on the mandrel. I basically hammered all over the surface and then polished it smooth, leaving a diagonal ripple pattern on the surface. You can even do things like drill hemispherical holes and then roll it flat, or punch holes and grind it flat to make concentric rings. Check out patterning techniques for Damascus steel if you want to see other ways of patterning mokume, and good luck!

[kyle.marsh]

Alright, that's what I suspected. Thanks for confirming!

[AsianSpanker]

This is a tough economy, That is a lot of money. Do you have something using nickel, copper, Sterling silver, or such metals to practice on? What you have given here is more of a business start-up or a rich persons project. I believe that it isn't in the tradition of this forum, or maybe it isn't in the tradition of this forum as how I view it. Wonderful work though. Anything that starts with buying gold in this economy isn't something I am going to be following up on.

[hereiam]

Actually, you can save about 80% of the cost of this project by switching metals. See the note at the beginning of Step 1:

"Note: You can substantially lower the cost of this project by using different metals, such as silver, copper or brass."

Nickel-silver, sterling silver or bronze would also work very well. That would also lower the cost of the solders used, bringing the cost of the project from the $2,200 range to the $400 range. That number goes down more if you can find/borrow tools from friends. If you can scrounge just a few things, like the sandpaper, steel, nuts & bolts and a hammer, you can bring it down to around $300.

[davebmiller]

Nickel can cause adverse reactions in some people, and is not recommended for jewelry. While not -the - most authoritative source, WebMD's article is at least a starting point. http://www.webmd.com/allergies/nickel-jewelry-allergy

A much better metal for a lower cost than gold is sterling silver.

[Aeryk1]

If you want to find less expensive already made billets, my favorite place to go is www.ReactiveMetals.com. ShiningWave has some materials, tips and uses mostly ReactiveMetals products, but they have some other items that will interest you. They have an interesting selection from less expensive to 22kt with 18kt called samidare. Mokume gane means literally wood eye metal which we interpret to be wood grained metal. To find out about more detail on making mokume gane metals you can go to www.faceters.com/askjeff/mokume.shtml. Rio Grande will custom make billets for you.

[JoeCools]

Has anyone else had a problem downloading the *.pdf file, Just wanted to see if there was a new source for the file or if possible could reload anew attachment of it?

Thanks
/Joe

[kentwidman]

One ring to rule them all.

[RubrDuckZilla]

good one

[jarell]

hah thats a good one hopefully smeagol don't get to them

[kmpres]

Fantastic work, and an excellent write-up! And you say you're not trained in jewelry smithing! You make it look easy, too. I have a two questions, if I may:

First, I'm intrigued by the Japanese names for the smithing techniques you used (moku means wood, gane comes from kane, which means money (originally made from precious metals), etc). The Japanese do many things exceptionally well but I wasn't aware that their precious metals smithing techniques were that well known outside of Japan. I presume that other countries have their techniques as well?

Second, I bought my own wedding bands in Japan 24 years ago and they have two layers, platinum and gold, with the platinum layer outside and a somewhat wider band of gold inside. My ring turned out to be slightly too big for my left ring finger so ever since our wedding day I have worn it on my right ring finger on which it fits just fine. I tried to have it adjusted but was told that the metals have different melting points and cannot be resoldered once they are cut for resizing. Yet you carefully detailed a technique that solders multiple layers of dissimilar metals without any problem. Am I missing something here?

You make a lovely couple, by the way. I wish you both much joy and happiness!

[Ole bally]

Kmpres. Without having to destroy your original wedding band, If you were to have another gold band made that fits your finger properly and then machined on it's outside so that it is microscopically larger than your current ring, dip the new ring into liquid nitrogen whilst gently heating your original ring in your stoves oven. be careful how much heat you use...it must not get hot enough to discolor the metals. The quickly drop the new ring into the old on a flat glass surface to align them perfectly. Once they get back to room temperature...they will never move again! Good luck! :)

[kmpres]

Good idea.  I'd actually thought of that some years ago but decided it wasn't worth the cost, and the wife might object to my hiding the original engraving under a new band of gold.  The size difference is really minimal, maybe a quarter ring size, so it's not worth the effort.  Besides, there's an advantage to my wearing mine on my right hand and she wearing hers on her left. We can stroll hand-in-hand and our two rings would make contact symbolizing our love and devotion to each other.  Kanshoo-teki-ni narimasu, ne!

[Ole bally]

OK dunno if the last bit is a blessing or a curse!! It's just one way to solve your original problem! We use the same principle to put bearings onto shafts etc! I am pleased that you still deign to hold yr wifes hand after 24 yrs! Well done! Good marriages are very hard to find these days! Hang in there! 'Alles van die beste' !

[agthomas]

I believe the first application of mokume gane in Japan was the forging of very strong metal blanks intended to become katana, and other blades. A mokume gane sword is much less likely to shatter than a blade forged another way. Those swords can also be honed to an unusually sharp edge. Weapons were also made from "folded metal" in China and Korea.

Then, there are swords from the Middle Ages made from similar-looking Damascus steel blades (from the Middle East) and "damascened steel" blades (from Toledo, Spain). Today, there are "archeometallurgists" studying ancient forged blades to actually sort this out.

And of course, your non-lethal, hand-forged gold is quite gorgeous! Thanks for sharing the experience with us.

[kmpres]

Ah, I had thought that Japanese sword-smithing had something to do with it. Fascinating history, sword-making.  Nothing like a sustained war to advance the state of technology.  They found that if you heat, hammer and fold a blank 13 times you can create over 16,000 layers and create a tremendously sharp edge in the process. Japan is not all that well known for its jewelry making so the precious metals angle threw me off a bit but it makes sense that the two fields are related.

[hereiam]

Thanks for the nice comments, kmpres!

You're right on the Japanese name - moku=wood, me=eye,see and gane=metal,money. I'm not sure when mokume hit the international scene, but I don't see it as often as I'd expect to, even nowadays.

And as for your rings from Japan, they are correct that cutting (to resize) and re-soldering would be difficult. I made a diffusion bond, which was made possible because my metals could be held together at a very high pressure. Flat sheets or squarish billets are perfect for that sort of setup. I don't know if one could hold two ends of a ring together to make a strong diffusion bond. In addition, platinum melts about 700C higher than gold, and I don't know if gold solder would wet platinum metal.

Finally, with some metal combinations (luckily not Au-Pt) you run the risk of melting a eutectic alloy that forms between the two metals. This is an alloy with a lower melting point than the original two metals. Many solders are made this way, so that they melt at lower temperatures. Part of the reason I used all 14kt golds is that making a eutectic alloy at the interface wasn't a concern.

[kmpres]

Thanks, that solves a 24 year old mystery for me. My rings are 18Kt gold and Pt900 platinum. I suspect they were made from two closely sized rings that were joined by heating both to near the melting point of gold so that when the platinum ring was placed over the gold, and both were allowed to cool, they contracted at different rates which provided the high pressure for the bond.  At least that's been my guess all these years.  

They also told me that it was unlucky to cut a ring after it'd been forged as that could symbolize the eventual breakup of the relationship so it was best that I not pursue it.  Sage advice, I thought.

[ToolboxGuy]

I've had to cut off my wedding ring or lose the finger. The ring probably saved my hand from getting fingers/knuckles broken, but folded under the strain. We talked about having them melted down together and reforged into new rings/designs, but never got to doing it. Still have the wife (and the ring) 20 years later.