It sheds green sparkles every time I touch it. Mica mines operate near here, which makes me think this is a chunk. Very shiny.

What could it be? A few other gem species are forming what I think are hydrates. They've been in a room temp, somewhat humid environment and are growing yellow crystal material.

Found it on the coast of France during a vacation a while back.

A friend and avid rock hound sent this for my natural pigment experiments.

Now to figure out how to grind it down, it's harder than I thought.

Bonus black light pic:

Not sure if rules allow for painted rocks but this one from my kid is the coolest rock ever!

Magnified view

And another random stone with lots of strange eyes and mouths

Now I just need to find an Eevee....

(side view to show off his layers)

He looks terrified of something... What does a rock have to be scared of?

From the other side:

A subset of rocks we found at our beach.

Edit: GiantChickDicks suggested to check under UV light. Funny you should presume I have such a device:

The faint highlights are a camera artifact and look much dimmer to the eye.

Picked this bad boy up from a local oddities expo. Aurora quartz is natural quartz that has been bonded with metal vapor in a vacuum chamber to give it an iridescent shine

Asking folks so I can clarify the rules.

Rocks and minerals are pretty fascinating, quite a few discussions pop up in the comments about geology — We could all learn together with some science peppered in.

At the same time, I really like the vibe of mostly sharing rocks, encouraging people to go rock hounding for the hell of it. ~And~ ~I~ ~already~ ~have~ ~three~ ~news~ ~coms.~

Alternatively, we could partner with or make a geology com for the science and news side of things, keeping this community focused on the rocks.

The questions:

• Should we include articles, discourage them, or have a rule against them?

• If we don't want articles, should we partner with or create a partner community for articles and science?

edit: I'll leave this up for about a day and amend the rules sometime over the weekend based on vibes and feelings, not going by votes or volume. I can always change things around again if we're not happy with the rules.

edit: Thanks everyone. I changed the sidebar text to encourage cool rock posting, with facts and articles in the body.

Feel free to keep discussing the cool rocks community if you have ideas.

A friend gifted me these years ago after a visit. They had permission from an elder to take them, so they're extra blessed.

edit1: Some more photos of this selfsame rock through a micro scope (somewhere between 10x and 45x, didn't write it down)

and another feature I discovered: the rock has a slickenside which i can't really show on a photo. basically one of the sides is beat up into sand and polished. the whole rock unit was pretty beat up, so i'm not super suprised but it's cool

edit2: ok i tried to capture the slickenside

Here's another cool rock in my collection. Again, I have no idea what it is nor do I remember if I found in Oklahoma or here in northern California. I think it was Oklahoma?

I grabbed this one to give to my wife for obvious reasons. I have another heart shaped stone somewhere that's even better shaped than this, but I can't find it. We moved last year and a lot of things are still packed up.

I'm enjoying this cool rocks instance or whatever it's called. It's fun to learn about this stuff.

... and biscuit tins, I was too lazy to crop the picture. I have some really cool rocks that just aren't on display yet. might get some pictures of them for here later

Seen down by the river

Found this cool rock back in 2010 on the Sylamore Trail in northern Arkansas. I thought the stains looked like a cave art figure with arms raised.

I have many little cool stones.

Found this cool rock at lake Tahoe. It has 2 white rings around it that are so perfect I thought at first they were drawn. Now it lives in my Chia pet garden. Here's an additional pic.

The sandstone meets the tides and it's delightfully weird

You can have more than one favorite rock.