I picked up some wonderful rocks at the estate sale on Sunday. Yep, I'm a sucker for rocks. Big time. Just ask the sisters. I have boxes of rocks hidden all over Mom's house. You're welcome, Mother. Anyway, I cleaned my lovelies because you never know what sort of basement boxes these might have been in--they could have functioned as doorways for mouse houses! And as cute as that would be--oh, it would be cute--I'm going to say no thank you.
For most rocks, dish soap, warm water, and an old toothbrush will work just fine. That's what I used here. But if you're handling something delicate (as in, a bit crumbly), be sure to use care. Quartz is pretty hard, so I wasn't really concerned that I was going to chunk a piece off. And often, when you're cleaning crystal clusters, like this one, some of the crystals might detach. Nothing to worry too much about--I lost one tiny crystal to my vigorous scrubbing--just be aware that it's a possibility. And before you use something stronger than dish soap (like hydrogen peroxide or oxalic acid), make damn sure you know what type of rock you're dealing with. You don't want your precious find to end up dissolving right before your eyes. That would be a minor tragedy. Worse than dropping an egg sandwich.
Now, you may be looking at these pictures and thinking, Hold the phone. You said you cleaned these? Because I still see dirt. Well, you're sort of right. The dark stuff that looks like plain old dirt (Is there such a thing as plain old dirt? Not according to Science!) is actually mineral deposits, probably a manganese oxide here. And you wouldn't want to wash that away, right? I mean, it's part of your rock's heritage. And really, you'd find it fairly difficult to get rid of these minerals with soap, water, and manual toothbrush action alone. You'd need to make a foray into serious rock cleaning.
Most of the shiny perfect crystals you find in mineral shops have been professionally cleaned and cut to appeal to buyers. Crystals in their natural state are often considered less desirable. Ugh, giant frown over this fact. Not that I don't love shiny perfect crystals--I just don't love imperfect natural crystal less. But if you really want shiny perfect crystals, you can get there with a bit of work. Bob's Rock Shop has a good guide to cleaning minerals and a breakdown of how to procure the tools you'll require. Yes, you'll need tools, like acid, safety gloves, and dental picks. Fun!
Whether you're seeking geologic specimens in someone's basement or out in the field, happy hunting!