can a diamond dissolve in acid ?

Ok recently i was doing some testing about the chemical resistance of diamond with various acids, something interesting happened when the diamond was placed in piranha solution. some black particles are "coming out" from the diamond, and fates away as the particles were dispersed into the solution and some bubbles were formed (CO2 MOST LIKELY) this was taken place near room temp. I actually did not think it was possible for diamonds to react at room temp. Does anyone have a theory why it happens?
this is a video of the reaction : https://youtu.be/dgQf8trgDGY

Ahh, nice. I would have conducted this experiment in a few weeks.
Oh, I still might

My original idea was to burn a diamond in an oxygen rich flame from a propane torch.
Then I thought it'd be equally interesting to make one disappear in a liquid (Piranha was the first that came to mind).
And then I though about molten salts such as NH4NO3 or other oxydizers that'd only leave gas products.

With the miniature size of my (synthetic) diamonds I'll be able to perform a number of experiments so if you have ideas along the above lines, please do suggest !

maybe try pulverizing a diamond, mix it with potassium nitrate and sulphur and make diamond gun powder

Quote: Originally posted by Keras

It’s the only gemstone that cannot withstand a fire. .

Quote: Originally posted by unionised

Quote: Originally posted by Keras   It’s the only gemstone that cannot withstand a fire. . I'm not trusting you with my amber, pearls or opals.

Quote: Originally posted by elementcollector1

Heated amethyst turns anywhere from yellow to a rich brown, depending on the starting saturation. This is often sold as 'citrine'. Turning this back to amethyst requires radiation to get the iron back into the 4+ state. Amber and pearls are semi-precious, organic materials - not gemstones.

Quote: Originally posted by Keras

Well, pearls are organic in origin but mineral in nature (aren't they made of carbonate?). It’s like limestone: it’s made up of bazillions of exoskeletons or shells, but no one would call it an organic material.

Quote: Originally posted by MrHomeScientist

Heating amethyst can also produce green prasiolite! Natural prasiolite almost entirely comes from one small mine in Brazil. I've burned diamond before in one of my videos, although the setup was a little tricky. It's an awesome experiment if you have the chance to do it, not only because of the spectacle but because you're recreating the experiment that was the first to figure out what diamond is made of! So how did your diamond fare in piranha? Did it measurably dissolve?

Quote: Originally posted by zhonglanindustry

What is inside piranha solution?

Quote: Originally posted by Keras

Quote: Originally posted by zhonglanindustry   What is inside piranha solution? It’s a mix between concentrated sulfuric acid and concentrated hydrogen peroxide. It can oxidize about anything organic, so it is used as a last resort cleaner, especially for sintered glass funnels.

Manganese heptoxide? Yikes! Does it clean the frit by exploding it into pieces too small for dirt to stick to?

[Edited on 8-24-2018 by MrHomeScientist]

Quote: Originally posted by fusso

Why not use cheaper uncut diamonds?

Here is a seemingly crazy electrochemical experiment!

If you believe that a diamond electrode could be damage in electrolysis setting, then possibly, in an electrochemical battery cell, the diamond may be at risk also.

I am unsure of the anodic index of pure carbon, which is very noble, but if you placed it in say a sea salt/H2O2 bath with say a more noble constructed carbon-based electrode (see http://www.chem.ualberta.ca/~mccreery/RLM%20publication%20PD... and heterogeneous vs. homogeneous carbon electrodes briefly discussed at https://www.tandfonline.com/doi/abs/10.1080/0003271070124212... and https://www.permelec.co.jp/en/products/pdf/Diamond.pdf and finally https://en.wikipedia.org/wiki/Carbon_paste_electrode), it may corrode.

Diamond destroyed by galvanic corrosion, let me check my insurance policy.

On the bright side, you do now have Diamond Seltzer Water with a touch of Natural Sea Salt, which may be worth something.
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By the way I would avoid boiling your diamond in ferric citrate, ferric chloride or even Fe2O3. I believe a redox reaction is still unlikely on the surface of the diamond, but if yes, possible pitting,staining, discoloration,...

If you were experimenting with a more activated carbon, much more likely something would occur, but I am not totally sure if a diamond would always be completely unscaved. Source: 'Enhanced production of reactive oxidants by Fenton-like reactions in the presence of carbon materials'. Available from: https://www.researchgate.net/publication/276120744_Enhanced_...

Now, that source basically says it does not know the mechanism by which the reduction of Fe3+ by carbon occurs. It may, in my speculation, be due to local surface defects on carbon producing an excess of electrons with the Fe3+ acting as a ready receptor. On the particular surface of a diamond, harder to envision such a process, but it may be worthy of a test.

[Edited on 8-10-2018 by AJKOER]

Quote: Originally posted by Fleaker

Usually standard for cleaning (gem) diamonds in bulk is nitrosulfuric acid followed by HF to frost out CZs.