Cleaning Quartz?

[Mac]

Prospecting many years ago I discovered a large chunk of quartz with intact host rock on one side. The slate is flat and so, I want to clean the piece and display it. It's about the size of a shoebox. It's in my storage unit, otherwise I'd take and post a photo. From what I remember it's got pyrite in the cavaties and might be rather nice looking if clean. I use to be a medical laboratory technologist and very cautious about using chemicals without a safety ventilation hood, so are there non-chemical options? Would a baking soda or vinegar paste get it clean? Do I need to post the photo in order to ID how best to clean it? I have motivation now to tackle the major project of gutting the unit to get to the 40+ year collection of rocks, most of which are quartz pieces from gold bearing regions ... due to realizing just now that none of these have had a detector run over it. 

[DDancer]

A photo would be good Mac.  It'll let us have a look as to what you want to clean depending on the discoloration.  Could be as simple as a little vinegar, baking soda or some CLR but with what you've described I doubt you want to go as heavy as strong acids.

[Bob(AK)]

Depending on what you are trying to clean off of it, Iron Out may work from hardware store. Also a bead blaster

works fine on quartz, will not damage it

[Mac]

Thanks, DD and Bob. I should have waited to post the pics with the question. Pockets are not photographing well, too blurry. Some pyrite deep in there. Have read that pyrite can be a source of gold but that is only oxidized pyrite rather than intact, right? 

[DDancer]

Looks interesting.  With the pyrites present I dont adivse using strong acids or lime/rust removers as they will react with the pyrites.  I'd try bleach first for a week or so to see if it pulls out any organic stains.  After that try vinegar on a part of the stone for a week to pull out carbonates and see if that lightens up the quartz.  If you do decide to try acid dilute it to about 1 in 10 and try another part of the stone and see how it reacts to the pyrites.  Muritic *HCL* pool acid is fairly safe to work with but leave it outdoors and use gloves.