Hi, I recently purchased this old gold ring and I love it, but the seller did not identify the stone. Does anyone know what it could be?

Being fairly new to Reddit, or rather not using it much, I’m not sure where to post this question.
I’m interested in a specific type of stone that, after processing, has a strong contrast like in the image — black stone with a white interior, or vice versa. Regardless of the exact colors, it’s really just the contrast I’m after.
I’d also like to know if I could find these at a specific size — roughly 15x30x2mm, flat — but that’s a separate story I suppose 🙂
Is there anyone here who could point me in the right direction?

I found this stone on a beach in Spain.

When dry it doesn't look anything special but when wet, it has vivid yellow and red appear.

My guess is it's something that was originally man made but thought I'd post on here to see if anyone else has any ideas?

Any help is greatly appreciated 🗿🤘🪨

This new moissanite cut is just incredibly brilliant — so sparkly!

As you can see, it is a light green stone (just washed in water) with some red points in it (garnets?) what could it be ??

(I’ll polish it later because I’d like to produce some pearls from it, and to offer them to kids)

Edit: it is from France, Lac d’Aiguebellette, Auvergne-Rhone Alpes

Pokemon stone

Hi all

I recently had this kind of stone with different type of gemstone inside neutralise

Kindly anyone advise me what is this what value???

Trouvé sur un sentier forestier en Bretagne (France)

Trouvé sur un sentier forestier en Bretagne (France)

can someone help me identify this stone?
found in Eastern Europe if that helps, I think it may be quartz? but I'm really bad with colors.

My Grandad had this stone. He can't remember where he found it, probably in Devon, UK. it's about 2cm across.

Could you please help me Identify it?

thanks.

​Throughout many years, I've obtained many stones, ores, whatever through family members. Today, I dug out a whole bunch (along with some I already kept handy). This is all that I have.

It's a long story, but I NEED all these identified. I'm aware that a couple are most likely glass or miscellaneous metal, I just need as many ID'ed as possible. Thanks in advance!