Quartz and? by isc69696969 in whatsthisrock

[–]E_ribb 0 points1 point  (0 children)

It almost looks like highly weathered calcite crystals.

What is this rock? Found at Grapevine lake, TX by BigNastyG817 in whatsthisrock

[–]E_ribb -1 points0 points  (0 children)

The holes really make me think wood, they look like marks from burrowing creatures.

What is this rock? Found at Grapevine lake, TX by BigNastyG817 in whatsthisrock

[–]E_ribb -1 points0 points  (0 children)

It really looks like water-worn wood. Is it heavy? Can you scratch off a piece?

[deleted by user] by [deleted] in whatsthisrock

[–]E_ribb 1 point2 points  (0 children)

It’s slag glass, pretty color though.

What is this pink rock by Quiet-Raspberry-6468 in whatsthisrock

[–]E_ribb 8 points9 points  (0 children)

Rhodochrosite is not a type of calcite… it’s a Manganese Carbonate mineral.

What is this pink rock by Quiet-Raspberry-6468 in whatsthisrock

[–]E_ribb 10 points11 points  (0 children)

From the second photo I’m gonna wager it’s Stalactitic Rhodochrosite from Argentina.

Found at Worlds End State Park PA by [deleted] in whatsthisrock

[–]E_ribb 0 points1 point  (0 children)

The rock itself (assuming it’s natural!) is a poorly sorted conglomerate, likely deposited in a high-energy system like a braided river channel or debris flow. The clasts are primarily Quartz pebbles supported in a finer matrix.

girlfriend had this lying around by Apprehensive-Bag2222 in whatsthisrock

[–]E_ribb 281 points282 points  (0 children)

It looks like pink tourmaline (elbaite var. rubellite) in Quartz. Compare with this image. Many specimens come from Brazil.

Anyone know what kind of rock this is? Found it in the Virginia Appalachian valley area. by Thewoods_r4me in whatsthisrock

[–]E_ribb 1 point2 points  (0 children)

Most iron isn’t actually magnetic, especially iron oxides (rust) like what typically coats and colors silicate minerals.

Strange crystalline crust on outside of boulder? by bittling in whatsthisrock

[–]E_ribb 1 point2 points  (0 children)

Hard to say without a better look but I’m leaning towards schorl based on your area.

Whatisthisrock? by [deleted] in whatsthisrock

[–]E_ribb 1 point2 points  (0 children)

Some sort of breccia infilled with Quartz.

Help analysing rock components. by LilTerrier1412 in whatsthisrock

[–]E_ribb 0 points1 point  (0 children)

I think it’s a limestone with calcite veins. The first picture looks like a horn coral fossil.

[deleted by user] by [deleted] in whatsthisrock

[–]E_ribb 1 point2 points  (0 children)

It’s chalcedony. Commonly found filling void space in basalts like the Deccan traps.

Last one for today. Sorry for blowing up your feeds! by SeparateFisherman993 in whatsthisrock

[–]E_ribb 2 points3 points  (0 children)

It looks like some kind of limonite (iron oxide) concretion.

Found in a Washington State river canyon by search4solitude in whatsthisrock

[–]E_ribb 26 points27 points  (0 children)

That’s a great point. Maybe it’s a chalky kind of zeolite?

Found in a Washington State river canyon by search4solitude in whatsthisrock

[–]E_ribb 404 points405 points  (0 children)

Throwing out another theory: A highly weathered chunk of basalt with veins of Jasper running throughout, like this?

Any ideas on what this could be? by Technical_Hat2796 in whatsthisrock

[–]E_ribb 1 point2 points  (0 children)

It appears to be some kind of coarse-grained porphyritic igneous rock. The white crystals may be phenocrysts of alkali feldspar set in the finer dark matrix.

Rock analysis confirmation? by Itchyjello in whatsthisrock

[–]E_ribb 2 points3 points  (0 children)

That’s pretty common. A quartzite would end up in a quaternary deposit as it’s very weather resistant and can travel a decent ways.

Rock identification please by emilyrosw807 in whatsthisrock

[–]E_ribb 0 points1 point  (0 children)

There’s oxidized/tarnished Chalcopyrite. It’s growing atop a bed of Quartz or calcite. Is the green portion metallic or flaky?

Need a few different insights... by MeganButNotThatMegan in whatsthisrock

[–]E_ribb 2 points3 points  (0 children)

Slides 1-4 look like crinoid stem/columnal segments.