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Rock tumbling, is there an economical substitution for grit & polish? . Answered

I have vibrating & rotary tumblers. The commercial grit & polish I've been using, comes in a 4 step process. Is there a homemade grit or other options for tumbling rocks & gems?    Thank you


Here's another response to this very old question You can buy silicon carbide sandblasting grit at any hardware store (same material that's sold as tumbling grit). They might only sell it in a couple of fairly coarse grades and only in big bags, but it might be cheaper than a hobby shop. For rock tumbling silicon carbide works because it's very hard and when it's crushed between two rocks it shatters into smaller but still very sharp grit that continues to work well.

i realize this is an older post but hopefully this will help someone now i am not a rock polisher but i am a rockhound so tumbling is a little bit of an interest of mine anyway albert.zabinski.3 is right about sand being to soft except you could possibly use fine sand for the pre polish stage but idk anyway one thing i know you coud use for the rough stage and possibly more depending on how far you take the crushing process is angle grinder wheels these break apart easily with a hammer(wear safety glasses)and can be acquired for free from many metal shops or prety much any factory or construction sites since when they wear down they just throw them away so not only would you be saving money you would be reusing something that would normally end up in a landfill. Thank you and if someone happens to try this i would appreciate any feedback on how it works out

sand is way to soft hardness of 7 - 7.5, normal grit is silicon carbide is much harder at 9 to 9.5 on the mohs scale. To get a better price you need to buy at least 25 lbs, 50 is better, if doing a lot of tumbling. Best prices are a 300lb. barrel. I know buying in this quantity is a large chunk of change, but try finding a friend or 2 to split the cost or check your local lapidary club. They may already buy in bulk and resale to members at the discounted price. Silicon carbide is the best tumbling media for rocks.

Sand, which is mostly (if not completely) quartz. Quartz has a hardness of 7. You could tumble Amethyst, Quartz, and all other substances with a hardness of 7 or above for months and see no change at all.

may I suggest Harbor Freight? They have discount grits, it may only be a dollar or to but it could be enough for you?

I make my own grit which works fine but the only downside is that it take longer to polish than regular grit. I use a mixture of flour,sand,salt,and fine crushed rocks.

Lets analyze what you want:

1. Cheap polishing
2. A range of cheaper materials to polish stones varying from coarse to fine

OK None of this is tried BUT

There are lots of things round the house that are polishes. Some polish because they contain wax which fills in the cracks Some polish because the are abrasive. Metal polish.

So coarse polish - Some sharp sand from the builders merchant.

Followed by some round sand from the beach for a finer cut.

You could grade the sand by washing on a sloping rack just like the pan fro gold.

Sea shell tends to be softer because they are essentially chalk.

Down to the finest grit you probably have at home metal polish.

I can buy wax blocks loaded with grit at what I think is a very competitive price so if you go to an on line wholesaler you should be able to get polishing grits fairly cheaply.

Just as an aside you do filter off the grit when you clean out the tank don't you so you can use it again?? It isn't waste once it is used and should last for many operations. in fact all it does is effectively get finer.

Over all it doesn't look all that expensive - at least here in the UK.


The grit and polish you've been using is made of silicon carbide and is much like silica sand (used in the sandblasting industry). Its primarily made with quartz.

Polishing grit comes in the 4 step process that you're familiar with because its acting like various grits of sandpaper. You need a blend that's like coarse salt, a couple medium grits like sand and finally a grit that feels more like powder.

It is possible to make your own grits, but it does require a lot of manual labour to bring the material down to an even grit consistency, using screens to filter the material as you go. Having even one large grain within your finer blend will result in scratches.

You may want to consult a sandblasting company in your area and enquire about the products they use and find out where they are obtaining their material.

Try lining your tumbling pot with wet and dry paper such as you might use to rub paint down with - BUT choose a water proof one. Just a simple liner should produce reasonable results if you A) keep the volume of the contents low b) don;t expect a full professional finish as per the large range of grits normally used.

AND on the other hand the sea does a wonderful job with just a few hand fulls of sand!

Sand is an excellent idea. But it's got to be graded to size. Any larger chunks will just make scratches much deeper than the smaller grains.