FMF - Friends of Minerals Forum, discussion and message board

[barbie90]

I will make an experiment, so I want to know which acid dissolves quartz?

[lluis]

Dear Barbie

Do you know that such acid causes extremely painful and difficult to cure wounds?

I would not be very eager to do so, unless you are an experienced chemist and you have the appropiate laboratory.

With best wishes

Lluís

[chris]

Hi ,

I do agree with Lluis. I have a biochemistry background and was quite used to manipulating acids. The only one I know working with quartz is extremely dangerous to handle and should be handled only by trained people using proper equipment.

I think it would be wiser for you to avoid it.

Christophe

[Peter Megaw]

Barbie...I will (unnecessarily) reinforce the others. This is a real "Trained Professional, do NOT attempt this at home" situation. This is a very nasty acid...not the least because it is not particularly dramatic in its effects...but a drop or two on your skin can wreak havoc.

PLEASE, if you insist on going down this road, find a chemist with a full fume hood, full protective gear and proper tools and vessels for handling it. This acid will dissolve glass also

[Gordian]

The only acid that I know of that might do the trick, because it does work on glass is hydrofluoric acid, which is really a very nasty chemical. It is very corrosive to the skin and the fumes are very toxic. Not something that one plays with generally.

c.rhodes

[Vinoterapia]

Hello Barbie.

You may think that all these guys are being cautious with the use of the acid. But to put you an example, if you have ever watch one of the "Alien" movies, you may recall how the "blood" of the alien dissolved the metals and drip all around the spaceship. Well that is how your skin and flesh will melt under a couple of drops of hydrofluoric acid, while the fumes will do something similar in your lungs.

Please do not use this acid.

José Luis.

[Tracy]

Wholeheartedly agree. Hydrofluoric acid should only be handled under controlled conditions such as in a laboratory, and while wearing appropriate personal protective equipment. Not to mention the special precautions which should be taken for storage and disposal.

- Tracy

[barbie90]

ı used nitric acid on some minerals which ı thought to be corundums ,once upon a time a geology student advised me to use every kind of acid on corundums because they wouldnt be effected by any kind of acid ,ı poured nitric acid on my specimen(ıf corundum or not ı still dont know)all of them made fizz only one of them dissolved ,so if they had been corundums would they have made fizz or not?

[lluis]

Good afternoon, Barbie (any name?)

Nitric acid is also a nasty acid. It produces the xantoproteic reaction, and unless you like to have yellow spots on skin, well, better let for trained ones..... (besides, apart of decoloration, wounds are produced)
Diluted hydrocloric acid, muriatic acid if you prefer, serves for same and is not that bad. But not exactly good. Vinegar is good enough to see fizzing (that is decomposition of a carbonate...) and is lots more safer.

Corundum will never fizz with an acid
Corundum is aluminum sesquioxide Al2O3.
With and acid, time, patience and a lot of luck, you will get the aluminum salt of the acid plus water. No fizzing.
If something fizz with an acid, or a metal or a carbonate. The metal, it depends which. But taking in account that the normal ones found as native do not fizz with a normal acid...., is a not so bad simplification: fizzing with acid, then a carbonate.

May I ask you to place what are you looking for?
Maybe we can help if you disclose to us that.
If not, I fear that would be a long and tiring chemistry teaching.... :-(

With best wishes

Lluís

[Peter Megaw]

Barbie...whoever gave you the advice to just pour on any acid you can think of sounds seriously irresponsible....especially if you do not really know what you are pouring it on. There are fairly common minerals that will liberate LETHAL fumes on contact with nitric acid, and residues from one treatment may cause completely unexpected...and undesirable reactions when you go to the next acid.

Get yourself a copy of John Sinkankis's (out of print, so this is not a commercial) "Gemstone and Mineral Databook" and read his section on cleaning minerals. ..and PLEASE make sure you know what you're dealing with mineralogically before you start. I am not talking about using dilute HCl here for checking carbonates, but real reagents.

[barbie90]

Hello thanks for the advises, I will read the book

[barbie90]

this is really good to hear that you have a biochemistry background my sister is a biochemistry teacher at university too ,we poured nitric acid together ,she said this is not a problem acids are not harmful when its compared to .alcalis ,she said only pouring water on acid can be harmful ,now ı have nitric acid and hydroclauric acid in my home ,but ı want to know something if one specimen coated with mica or limestone it will make a fizz even in vinegar so how one can identify the specimen?it means that specimen comes from sedimentary rock but maybe limestone make the fizz?it comes from maybe volcanic place so how one can know?

[Dahlia]

Quartz may be slowly dissolved in hydrofloric acid.
It may dissolved more slowly in a boiling solution of sodium carbonate or a boiling solution of common salt and bleach.

[Tracy]

[Riccardo Modanesi]

Hi to everybody!
Hydrofluoric acid??? It is very very dangerous!!! It develops silicium tetrafluoride, which is very damageous for our lungs if breathed!!!! And generally I always advice non-destructive proofs for identify a mineral. The only chemical proof I do is chloridric acid for calcite, other proofs I do are physical (i.e. hardness, refractive index, specific weight etc).
Greetings from Italy by Riccardo.