loading

Rochelle salt is a fascinating easy to grow crystal that exhibits piezoelectric and ferroelectric effects.

This instructable will walk you through making your own Rochelle salt from baking soda and cream of tartar. And also show you how to clean your cream of tartar which probably includes some cornstarch.

I have seen a lot of information some good, but mostly just a recipe to follow which I never find entirely satisfying... Do this because I said so doesn't help me understand.

While researching on the internet I could see that the Rochelle salt recipe does not appear to have changed much since it was first transcribed from some book. There was little discussion about theory or properties, beyond it is piezoelectric and this is the recipe.

Showing you how to mix the salt is but one step in exploring the crystals.

From Wikipedia
Potassium sodium tartrate tetrahydrate, also known as Rochelle salt, is a double salt of tartaric acid first prepared (in about 1675) by an apothecary, Pierre Seignette, of La Rochelle, France. Potassium sodium tartrate and monopotassium phosphate were the first materials discovered to exhibit piezoelectricity.[3]

...

Rochelle salt is deliquescent* so any transducers based on the material deteriorated if stored in damp conditions. It has been used medicinally as a laxative. It has also been used in the process of silvering mirrors.

...

The starting material is tartar with a minimum tartaric acid content 68 %. This is first dissolved in water or in the mother liquor of a previous batch. It is then saponified with hot caustic soda to pH 8, decolorized with activated charcoal, and chemically purified before being filtered.

So the highlighted bit says Rochelle salt is made industrially by dissolving cream of tartar into solution and then neutralizing with Caustic soda (Sodium hydroxide) to pH 8.

This isn't the common method on YouTube** and Instructables

So I started searching, knowing there is usually more than one set of precursors. I ran across a couple old indirect references, like a discussion around the turn of the century regarding alum based baking powders vs Rochelle salt based powders... It hadn't occur to me till reading it, that is exactly what a sodium bicarbonate and tartaric acid baking powder would make. Modern non alum baking powders may use other recipes, like mono-calcium phosphate.

So what I have found (again) is this, an example of a "lost" technique. In that 1 version of this recipe is being copied and spammed as if it were the only way to do a thing. Were I trained in chemistry I might have immediately seen this.

The internet doesn't know as much as books, or actual chemists, about some things still. While the typical method of converting to washing soda does lend itself to lab techniques better than store bought baking soda... nobody is measuring the weights for it to matter.

A very very thorough blog about Rochelle salt and its history also using this recipe also the place I ran across cleaning the cream of tartar http://www.extremenxt.com/blog/?page_id=77

** a number of YouTube videos these days are about some free energy nonsense using Rochelle salt and/or Epsom salt to make a simple electro-chemical cell and thinking they invented something over-unity. If you are using dissimilar metals you made a battery. Crystals that precipitate in water still contain water making them a rather concentrated electrolyte. In this case Rochelle salt holds 4 water molecules - tetrahydrate. When you put 2 different metals in contact with this you create a voltaic or galvanic cell. These work like the lemon or potato clock science experiment from school.

Step 1: Chemistry

Rochelle salt can be easily produced through at least these reactions;

KC4H5O6+NaHCO3=KNaC4H4O6+CO2+H2O (cream of tartar + baking soda = Rochelle salt + carbon dioxide + water)

or

(2)KC4H5O6+Na2CO3=(2)KNaC4H4O6+CO2+H2O (2 cream of tartar + washing soda = 2 Rochelle salt + carbon dioxide + water)

or

KC4H5O6+NaOH=KNaC4H4O6+H2O (cream of tartar + Lye = Rochelle salt + water)

Traditionally you mix the tartaric acid in near boiling water to get as much of it as possible to dissolve. Then mix the alkali in slowly.

Adding baking soda to hot liquid is not very exciting, adding lye to hot liquid on the other hand is. Don't do this quickly

Washing soda and lye are caustic and irritating, they also heat up when added to water. You could have a potential steam explosion like event if you dump lye powder into too hot an acidic liquid. The overall reaction has a negative energy it requires heat from the environment.

The enthalpy of solution (fancy way of saying how much the temp changes when dissolving stuff) for the 3 given alkali reactants are

Lye -44KJ/m This releases 44 Kilo-joules/mole when added to water if we had 100g of water the temp would go up ~6 degrees °C

Washing soda -28KJ/m this releases 28KJ... this temp would go up ~2 °C in 100g of water

While baking soda at 17KJ/m absorbs energy from the water to dissolve. This means the temp drops slightly.

Also of note Rochelle salt has a positive enthalpy like baking soda. I was unable to find this number, but know the solution got colder when dissolving the salt.

Rochelle salt melts at 80°C-100°C (176°F) *sources have some disagreement, but its below the boiling point of water.

Solubility charts are quite informative, the chart I included is the data I found on solubility, and hre is another chart. http://shodhganga.inflibnet.ac.in/bitstream/10603/... this whole chapter is a decent read, it also includes a diagram of a scientific crystallizer that's in use today.

At 25°C you can dissolve equal weights salt and water, at 45°C you can dissolve 200% of the weight in salt in water.

Fractional crystallization and washing first with ice cold water then with a non polar solvent like isopropyl alcohol have yielded me slightly cleaner results, but nothing beats pure reagents before it becomes this super water soluble salt.

Step 2: Gather

For the % of us still using imperial measurements. I will try to include Fahrenheit degrees where I remember but you can do the ounce/fluid ounce conversion yourself. It just makes chemistry harder than it needs to be to also add a unit conversion.

Glassware - 2x something large enough to hold twice the volume of your recipe.

A stirring stick - ideally glass or non reactive plastic, Stainless steel is probably ok

A gram capable scale - the range will depend a little on your batch size You can do this without a scale but its kinda irritating

coffee filters - or actual filter paper if your inclined/lucky

A hotplate or stove

A food thermometer (something that will measure up to boiling. a meat thermometer could work in a pinch)

Stove safe pot to use as a double boiler for your Glassware

(Recommended) purifying your cream of tartar you will also need

A .5L (2cup) microwave safe measuring cup

A microwave

A large container to hold the cooling tartar solution

Some space in a fridge or other cool area < 10c (50f)

A large flat glass dish for drying (pyrex cake pan)

Ingredients

1.Cream of tartar aka potassium bitartarate - potassium hydrogen tartrate - https://en.wikipedia.org/wiki/Potassium_bitartrate

2. Baking soda aka sodium bicarbonate - sodium hydrogen carbonate - bicarbonate of soda https://en.wikipedia.org/wiki/Sodium_bicarbonate

This reaction can also be done using washing soda, which most instructions will have you make from baking soda by cooking. The only advantage to washing soda over baking soda is you know there is no moisture in the weight when you bake it fresh.

This can also be done with Sodium Hydroxide - commonly called lye, a caustic somewhat hard to find and mildly dangerous chemical.

3. Distilled Water - some may be able to use tap water but this is generally just considered a nono when dealing with chemistry. Do you have fluoride or ammonium chloride in your tap water what about dissolved iron, copper or minerals? All of these will interfere to some degree and create unwanted byproducts.

Step 3: Clean Food Grade Chemicals

Cream of tartar is almost insoluble in water at 0.37g per 100ml at 20c and a whopping 6.1g at 100c compared to the salt we are making which can dissolve 100g of its weight at 25c.
Knowing this we can get pretty pure cream of tartar using the following technique which employs fractional crystallization. When you have many things dissolved in water, the least soluble tends to precipitate out first.

Also most things are more soluble in hot water than cold. This comes in handy all through making crystals.

If we add enough water to completely dissolve all the cream of tartar and then pour off the water. Anything that did not dissolve is insoluble in water and not the product we are after. One of my bottles of tartar had a much higher concentration of the even less soluble form of tartar. I had to add another 400ml of water to dissolve it all. you can also re use the water for purifying after it has cooled and most of the tartar has dropped back out.

Once the water is cooled most of the cream of tartar precipitates out while most impurities will stay in solution.

This is based on a 100g container of cream of tartar, as long as you keep the water to powder ratio about the same for this step it will work. With this volume of water depending on how low a temp you go, you are losing 2g or less of the tartar per 25g going in. Anything else lost is going to be impurities.

I modified this recipe from 600ml for ever 37g of cream of tartar.

Purify cream of Tartar (credit for this step goes to M. Gasperi)

  1. 25g Cream of tartar + 450ml distilled water in a Pyrex container
  2. Bring to a rapid boil in a microwave oven
  3. Let stand 1 minute and then stir
  4. Bring to a second boil
  5. Let stand 1 minute and then stir
  6. Bring to a third boil
  7. Let stand 1 minute but do not disturb it this time
  8. Gently pour off just the liquid into a large bowl leaving any solid residue
  9. Repeat step 1 adding to the residue already in the container
  10. Repeat steps 2 to 8 but you can now discard all the residue
  11. Allow the bowl of combined liquid to come to room temperature
  12. Refrigerate the liquid for at least 10 hours down to at least 10C
  13. Occasionally stir just to knock down any crystals floating on the surface
  14. Gently discard just the liquid
  15. Keep the residue which is pure Cream of tartar
  16. Completely air dry, any moisture will throw off your weight measurements

The pure Cream of tartar forms as tiny beautiful glittery crystals. The amount you recover depends partly on how good your tartar was to start with. I typically lose about 12% by weight since contaminates are thrown out in the solid residue and also dissolved in the discarded liquid. Starting with 74g you might only end up with something like 60g of pure dry Cream of tartar, but that is still enough to make about 90g of Rochelle salt.

I think most baking soda is pretty pure since bicarbonate is cheap. You shouldn't need to clean your baking soda, but if your soda yellows when baked to washing soda then you should get a different brand or clean it thusly.

Purify Baking soda

236 g/L (100 °C) of baking soda can be dissolved in water.

Use the recipe and process for cream of tartar above substituting 100g of baking soda + 500ml distilled water

To make the baking soda into washing soda simply cook above 60C (140f) Reading suggests temps in the range of 150-200c (300-400f) are quite acceptable for speed of conversion. Its not something you can really over cook.

  1. place baking soda/slurry in a pyrex cake pan or other oven proof glass flat container more surface area is better
  2. put in oven and turn on to warm/low
  3. cook at low till dry
  4. once dry, turn heat to 175c(350f)
  5. cook for an hour or 3 and stir once in awhile to make sure heat, atmosphere exposure gets to everything, the soda will change to a shiny pearly white when it is done.

Step 4: Practical

Washing 100g Cream of tartar yielded me 88g pure crystal with all the water I used and my poor handling this means my cream of tarter is actually fairly pure. But in testing I found out I could tell a purity difference the reaction with the unwashed taking longer and the resulting solution has a noticeable tan/yellow tint. The uncleaned tartar produced cloudy tan crystals without a lot of large monolithic growths.

To be properly usable this needs to be cleaned, and with Rochelle salts love for dissolving in water this is now not as easy as it was at the cream of tartar stage.

The cleaned solution was crystal clear and the resulting crystals are clear white which is essential if you were planning on using any of the optical or electrical characteristics of these crystals.

  • Measure your pure dry cream of tartar weight
  • multiply tartar by .45 and measure out this weight in baking soda (because of water wieght you may need more of this than calculated)
  • Or .21 for NaOH or .28 for Washing soda

  • multiply tartar weight by 1.3 and measure this out in water weight
  • For me this was 88g cream of tartar 110g water and 39.6g baking soda

  • in a 500ml (2 cup) pyrex container place cream of tartar (a 250ml (1 cup) will work but it fizzes up so you might lose some
  • add water

  • place on the double boiler and bring the water to 70c

  • once at 70c start adding baking soda, mix in small amounts slowly
  • wait for the bigger reaction to subside and repeat
  • cook at 70c while mixing till the solution is clear and there is nothing at the bottom
  • once the solution is clear pour through a filter **
  • set someplace to cool slowly.

SAFETY TIP: when filtering do not completely seal the edge, esp when using hot fluid, the air in the container has to go someplace and expanding air will spill your hard work.

If using a large 2 cup container you can mix in almost 1/4 of the bicarbonate at a time. Till the last 1/4. Even though you weighed things from here add in small amounts at a time and be sure it still causes a reaction.

*This took about 40 min for the cleaned tartar and 50 for the uncleaned which also had a little too much baking soda in the end.

**I filtered the solute then placed it back into the pot of the now turned off double boiler and let the whole thing cool slowly overnight.

Step 5: Growth

Once everything is dissolved filter into a clean container and let cool,

If your solution is not water clear you still have impurities, it also may appear a little strange since it has a higher refractive index and is light polarizing. It should not have any yellow.To purify further simply grow crystals. Remove from the liquor, the crystals are cleaner that the solution.

When you have a decent layer of crystal growth stir the liquor and decant through a filter. If the solution is fairly pure I air dry the crystals in a tray at a slant so water can run off the crystals and dry away from them. If the solution is rather dirty, I will also wash the crystals with as little distilled water or clean liquor as possible.

After cooling the first batch, If you pull out 1 or 2 large good crystals and reheat the solution with the remaining crystal mass you can re-cool for more crystals. I suggest stirring and filtering.

You can do this a couple times until the salt:water ratio is too far from ideal, either you don't have enough salt to make useful amounts or your heating has driven off too much water from the batch and you get freezing transitions rather than crystallizing.

Simply put, water can only dissolve so much salt at a given temperature, or another way to say it is the maximum salt to water ratio is determined by temperature.

That simple thought has a lot of complex reasons and consequences.

As the temp increases more salt can be dissolved, as the temp drops the water has to let go of any excess salt.

If we remove water, either chemically or through evaporation the salt ratio increases, and solids precipitate out in response to equalize.

The practical application; if too many crystals are forming, or crystals are too foggy either lower concentration of salts, or cool even slower. Conversely, if crystal growth is pathetic try more concentrated solution. Crystal growing requires patience, but if a super saturated solution isn't growing crystals after 2 days it may need seeding.

Inorganic crystal growth tends to have a delay between supersaturation and spontaneous nucleation. Similar to super cooled water freezing when being poured out, the system can be outside of stable zones but not have enough energy to trigger. In the example above of no crystals after 2 days I have not managed to get a seed in without causing the rest of the solution to precipitate out excess.

The crystal for the cover photo was made by placing a seed in a just down to room temp super saturated solution. This makes it easy to make large somewhat poor crystals. There are too many inclusions and voids for it to be good for much more than sitting o a shelf.

Evaporation being a slow process allows time for the crystal to assemble well and is generally better at growing large crystals for those with patience. Dust free temp control environments are helpful. basements root cellars and other low temp swing environments.

The crystal used for the cover shot was grown by dissolving ~365g of rochelle salt crystal into ~250ml of water and then placed into an insulated cooler full of hot water. The huge mass of the water in the cooler and the insulation will slow down heat loss allowing for larger crystal growth to be possible.

With those amounts I expected saturation to occur around 36c and ~150-250g of crystal to precipitate out.

I determined this by using the solubility curve of the salt. I've seen a lot of these curves and they tend to vary for this salt by quite a bit. I think this may be related to the chiral nature of this crystal and differing solubilities of the enantiomers. Rochelle salt's solubility is pretty good, and rapidly increases as it heads towards its melting point which is around 75c.

sodium chloride (table salt) is an easy salt to determine solubility with its rapid crystallization and flat curve.

Just for a touch on the complexity, I wont really try to explain everything here, first I don't know it myself, and second there is a whole scientific discipline I (a layman) am trying to condense into a couple paragraphs...

Growing a crystal has been likened to a complex game of tetris. Micro crystals exist in solution and in proper circumstances will attach to a larger crystal surface. Unlike tetris this isn't a 1 way thing, there are plenty of orientations and a particular micro crystal could attach and detach many times looking for a proper fit. Micro environmental changes influence bonding. Most changes are resisted so there is a battle between many factors Example; by attaching to the bulk surface the local solution is now deficit and can hold more salt so the local area is now trying to dissolve the crystal, while diffusion from the surrounding area tries compensate. Simultaneously the crystallization releases heat which further decreases the effective salt ratio. The crystal is trying to form in an ideal structure to equalize energy micro states - something about the 3rd law of thermodynamics

Water is amphoteric, and does these complex hydrogen bonding things, its basically liquid magic. Its neutral, acid, and base simultaneously. ie H2O + H2O⇌(H3O+) + (OH−)

https://en.wikipedia.org/wiki/Amphoterism

When we dissolve salts in solution we are trying to achieve chemical equilibrium the anion and cation disassociate

https://en.wikipedia.org/wiki/Chemical_equilibrium

In un-stirred solutions you have diffusion and thermal variations ie there will be more salt at the bottom of the water column than the top. Unless you are using the evaporative method where the surface probably has the highest concentration.

Wiki https://en.wikipedia.org/wiki/Crystallization#Main...

Some of the important factors influencing solubility are:

Concentration:

Temperature:

Polarity:

Ionic Strength:

As you can see even a brief toe dip into crystal growth kinematics is a trip down a deep rabbit hole. Luckily we don't actually need to know all this to get large crystals.

The 2 main methods for growing crystals at home are cooling, and evaporation.

Cooling is good for seed crystals and rapid crystal growth.The slower you allow something to cool the larger a crystal you can grow within certain parameters. Induction period and metastable growth zone are easiest to affect by temp and concentration. eg Higher concentrations nucleate faster, higher temperature tends to increase the speed crystals can grow at to a point. too high a temp decreases growth rate and increases bulk defects. The commercial processes seem to focus on temps between 33-38c for Rochelle salt.


Step 6: Links and Reading

In order to do anything more than use Rochelle salt crystals as a laxative (its original design purpose), or a lab chemical you need to identify the active planes of the crystal. On 1 axis its electrically active.

The axis terminology for piezo crystals seems to normally be, either XYZ (planar) or when referring to cuts 000-111 (miller indices)

X is the electrical axis face to face across the center - Electrical input = mechanical deformation and polarization change This is the basis for piezo microphones, speakers, pressure sensors, and timing crystals*. These are transducers, to change 1 form of energy to another.

Y is the mechanical axis corner to corner across the center - Mechanical input = electrical output This is how a piezo lighter works, although it uses quartz which can withstand the tremendous shock required to generate 5-10k volts

Z is the optical axis 90 degrees from the 2 previous planes - many piezo crystals can be used as polarizing devices or frequency doubling with the correct cut and strong enough beam. A level of photon saturation is required to create the cascade that leads to second or third harmonically generated frequencies. In Rochelle salt this is the easy axis to identify. The crystal tends to grow much faster on the Z axis and If you didn't check really carefully you wouldn't notice the Z faces are not actually parallel

All links are the property of the respective owners and were merely found via google search and while every crystal system reacts a little differently the concepts from 1 usually apply to another.

A more detailed description of the crystal axes*http://www.instrumentationtoday.com/piezoelectric-transducer/2011/07/

MIT tells you how to grow crystals in simple terms - http://web.mit.edu/x-ray/cystallize.html

A very thorough blog on Rochelle salt and probably the source of a bit of my inspiration for sharing - http://www.extremenxt.com/blog/?page_id=77

Handbook of piezoelectric crystals - http://www.tubebooks.org/Books/hpc.pdf

The PDF links on uni-halle.de are the doctoral thesis from Dr. Christine Strege

http://sundoc.bibliothek.uni-halle.de/diss-online/04/04H318/

I really suggest trying to get a handle on the concepts discussed if you want to understand how to grow better crystals. While coming from the lab setting and assuming an expensive crystallizer the information is still applicable to understanding better ways to get higher quality with your setup. For student projects just temp control via a large thermal mass and evaporation is probably all that can be simply accomplished.

"state of the art" an introduction to the concepts and terms of crystallography if nothing else look at the pictures. http://sundoc.bibliothek.uni-halle.de/diss-online...

While about Epsom salt reading this and understanding any of it will help you understand some of the complex mechanics of crystal growth and the effects of various influencing factors. http://sundoc.bibliothek.uni-halle.de/diss-online/04/04H318/t5.pdf

Long and thorough discussing ADP/MAP and crystal inclusions http://www.minsocam.org/ammin/AM41/AM41_598.pdf

<p>While this explanation is indeed long I would not call it tedious, as it certainly held my attention. My thoughts were that I only wish my children had been exposed to science explained and demonstrated by someone like you, rather than the public and private school teachers they had- without exception I might add. How can we expect children to become interested in Science, Math Technology and Engineering (I mean those without an innate interest) when so many teachers either are not supported in their efforts to go outside the box and innovate, or else simply lack imagination or incentive to do so in the first place. Well done.</p>
<p>I grew up on Carl Sagan, Nova specials, and 3-2-1 contact. I see Bill Nye and Neil deGrasse Tyson as the replacements for this generation, but even with their efforts it seems S.T.E.M. is less popular than it needs to be. There is also an apparent lack of critical thinking being taught. The fact that people can go on the internet and argue for a flat earth is purely astounding. Poe's law may be at play</p>
<p>Agree S.T.E.M. are a neglected and underfunded application/learning experience in so many education systems all across our nation. Home schooling and sites like yours give us (those looking) some nice hands on, simple, and manageable projects (with fun/fascinating results) that will easily open the attitudes and desires for young people to apply themselves, and challenge themselves, and have excellent results. You have certainly inspired and pleased us, and we would like to say &quot;thank you.&quot;</p>
I'm afraid I must respectfully disagree with your description of yourself as a &quot;layman&quot;. ;) You may not have institutional certification or employment in the subject area, but your knowledge is quite beyond the level of a typical amateur or hobbyist, imo. Thank you for sharing it.
<p>If I Told you all ......Then it would not Be a Secret.....would it ?</p>
<p>Free Energy is Non-Existant. Regardless of the Chemistry Behind it. Know This, and Stay Thirsty My Friends ! LOL. In this Chemistry, One Must Have an appreciation Of Material Science, acquisition and Application of Pure and Applied Science. You Just Told Me All, i ever Needed to Know About This.....Thank you Very Much ! VJVMD</p>
<p>How to grow large crystals under more control: get container for the solution that can be lidded at top. Put saturated solution in with excess crystals on the bottom. Put container in constant-temperature room. Apply slight heat to bottom continuously. Tie seed to fine fish line and suspend in container toward upper part (pass lint through small hole in lid, and close lid). If you get everything right, the initial solution will be a little undersaturated initially, so will dissolve into the seed, removing stray tiny crystals on the seed, but not so much as to dissolve the seed off the line. The temperature gradient causes convection in the solution, the solids at the bottom to dissolve, and the seed to grow. As long as there are solids on the bottom, the growth can continue as long as desired. Growth rate is controlled by amount of bottom heat applied. Saturation can be short-term adjusted by altering total temperature (a slight warming at the start can be used to dissolve into the seed at the start). There is a Scientific American Amateur Scientist article about this, but you will have to order the CD to get this.</p>
<p>I am in fact exploring this currently, both an internal and external heat source have been considered I am starting with an internal for my own reasons. I was quite inspired by these <a href="http://chemconnections.org/crystals/intro.html">700 pound crystals</a></p>
<p>I Will Not Even Give you Guys a Hint. But, it is Brilliant. This is Why I Come to this Board, For Ideas. Then i Usually get Drunk, write them Down, and Forget about Them. This Time...Not So Much......Are We There Yet ?......Thought so. Peace &amp; Good Night !</p>
<p>I will Give an Example. So that a Future Shark Tank Entrepenure(sp), will Apply, use or Steal it, then Patent it, License It, and Make a Several Million to a Billion on it {IT}. I was Kidding. I won't Tell You. Based On the Electro-physics........One Without a Name Should have Figured this Out Already......LOL VJVMD</p>
<p>What do you Do with it, Once Made ?.......I heard of One application in the Comments, Not Being Snarky. VJVMD</p>
<p>I love your thoughtfulness and the fact that you explain many details of the journey. I would like to learn even more. As you write more about this, your thoughts will tend to organize, and you will fill in more details. I write technical material and have similar challenges. Now I start with a template (not for the project, but for writing about it) like they had in school: who, what, when, where, why, etc. Otherwise I forget to show people the basics of how it relates to them. I love that you are figuring out how to make this thing for yourself. I look forward to the next one.</p>
<p>Thank you for the kind words. </p><p>That is a great idea. organize the project before I start typing :) </p>
I look forward to reading more from you.
If only other instructables were this well researched and explained. You did a great job.
<p>Thank you for the kind words. </p>
Very interesting, however a long and tedious read. At the end of it all I'm still not quite sure why we should want to make these crystals or what we can do with them? Maybe a future instructable?
I apologize for the tedium, I do tend to go on and on :)<br><br>Well they are peizo elements we use them everyday in all kinds of things. although usually a quartz, or barium titanite ceramic. <br>My plan is to build a crystallizer and grow a crystal large enough to cut properly to make my own speaker/earpiece for a crystal radio set. There is a youtube video from another gentleman (rimstar.org) where he uses an uncut crystal for a speaker you can see here. https://www.youtube.com/watch?v=R7zjfaPKMSE<br>An uncut crystal has a terrible performance by comparison.
Thanks for the extra info, and by no means do I intend to come across as insulting. I re-read my earlier post and it sounded much harsher than I meant it to. So I apologize for that. What I should have said was your instructable is filled with excellent info, but it would be better served by organizing it into more digestable sections. It really is fascinating stuff though, so please continue and do share your new discoveries in the future!
<p>No worries, I didn't read it as insulting, I agree about it tending towards tedium and being overly wordy.</p><p>I also agree about digestible sections. Something I have trouble managing. I have so much information I want to share like the sourcing and history of any given fact. Or why I concluded X etc... </p><p>I probably spent longer editing than I did writing and even then I agree, what I have presented is a bit messy. Maybe if I had separate 'ibles one on growing crystals and one on the specifics of Rochelle salts for example, would make this more concise.</p>
<p>I have to say I detect some bitterness in your presentation, but I haven't concluded why. JMHO!</p>
<p>No bitterness is intended, I am simply not the greatest author/communicator. I see how my last paragraphs for example could be read that way.</p>

About This Instructable

19,818views

231favorites

License:

Bio: Just a guy in a place doing stuff. I have always been interested in science. I was the child my parents were worried about leaving ... More »
More by MakerIan:Adjustable Equatorial Wedge (Telescope Tripod Meade ETX60/70) Baklava Oven Fritata, crustless quiche, Savory egg pie 
Add instructable to: