Re: cleaning smokey quartz?
It depends on what you are trying to remove. Both acids will remove iron stains. Muriatic is faster (a strong acid) than oxalic (a weak acid). Both will remove lime, but muriatic has a definite edge. Super Iron Out from the hardware store will also remove iron stains and is much less hazardous. If you use muriatic acid, dilute it about 2 parts water to one of acid. Then let your crystal soak in the solution for a few days. Check it regularly for progress. The acid will not harm the quartz. Oxalic acid is dissolved in water and again soak the crystal. Both are hazardous.
If you use acids be careful. Use them out of doors, not inside! Wear eye protection goggles (not spectacles). A plastic or rubber apron is a good idea. If you get any on you, flush with running water for several minutes. If you get any in your eyes flush with running water for at least ten minutes, then get to a doctor. A spill on your clothing, get out of the clothes and flush the skin underneath with running water.
From Don Peck - January 24, 2008 at 08:03:53