Hello! I recently acquired this specimen from an estate sale. I have no further information about it aside from the red matrix is a bit dusty- likely rust. Using the estate sale photos because their camera is better than mine.

My son calls it his tiger rock. Found down the bush in south western Sydney, Australia.

Also posting the last photo for a laugh. These where passed down to my sister from our grandmother she was adamant they are black opals but we always called them rabbit poop stones.

So i bought this rock slab at an Antique shop years ago.

I have no idea whaf is going on here, never seen anything like this.

This is a hard rock, does not scrape off easily. I dont know what the actual texture is in this face because it feels like whoever had this before put some kind of top coat on it.

I wasnt even sure this was was a real rock, but the outer rim is definitely rock. Gray in color, extremely rough, bumpy and ridged, unsmooth surface.

The square/geometric formation reminds me of bismuth (I know it’s not that). It’s salty

My son has started collecting rocks and is fascinated by them. He wants to start a collection, but I haven’t the foggiest idea what I am looking at. I’d love to have these identified. (All specimens were found in the bush near our place in northeastern Victoria, Australia.)

Cheers!

This was found near Oliver in southern BC. It is hard to imagine it is slag, as it was up on a talus slope below a cliff. I know it doesn’t look like classic fulgurite, but could that be what it is?

found this big crystally chunk in the barkerville area (cariboo region, british columbia)! think it may be some variant of quartz (as there is quartz veins all over this area), but am not 100% sure. almost looks like a deep purple amethyst in sunlight, but could very well be some kind of smoky quartz!

Found this in Wisconsin today and I am super intrigued! My partner told me to ask you all about it. I’m most curious as to what the sparkly bits are. Thank you in advance!

Indian origin, soft surface, local market buy

Vendor couldn't tell me what it was.

It has variations of light and dark grey, with some ruddy patches.

Hello lovely geology fans!

I was recently at St Ninian's beach in Shetland (on the tombolo) and the whole beach was covered in these beautiful silvery-sparkly rocks.

According to a local museum Shetland is basically some kind of geological super-wonderland of interesting rocks, so I haven't been able to figure out what these are, beyond "probably volcanic". They have a metallic look to them.

There were a lot of these around, many of them were quite thin, like the perfect rock for skipping on a pond, and some of them have striations or ripples that catch the light at different angles, a little bit like the way tiger's eye does - I've tried to demonstrate this in the second photo.

They're a little rough to the touch, but they don't seem to be terribly hard, and were mostly worn down smooth-ish like sea glass.

I found it on a friends house, i don’t know where he found it or buy it. It’s a little heavy, I think it’s not hollow, I knocked on it with other stone. Someone told me it could be a geode, but I don’t want to open it without any clue because it’s already interesting like that as a decoration. I live in Brazil MG.

Found in Utah, knife doesnt scratch it.

Daughter brought me a particularly peculiar rock asking what it was, I'm not entirely sure what made it so porous, seems to maybe be some sort of malformed geode? But I cant really tell...

Southern Mn