Yo, Faithfree! (Big pix.)

[Gawdzilla Sama]

What's going on here?

[JimC]

FF has to lick it to fully identify it - it's a secret geologist technique...















(they don't just use it for rocks...)

[Gawdzilla Sama]

[Faithfree]

That looks like my kitchen. I tried microwaving some wet rocks recently (didn't work).

[Gawdzilla Sama]

That looks like my kitchen. I tried microwaving some wet rocks recently (didn't work).

So what do I have there, and what the hell made it like that?

[Faithfree]

That looks like my kitchen. I tried microwaving some wet rocks recently (didn't work).

So what do I have there, and what the hell made it like that?

Looks like chert, which is a sedimentary rock composed of microcrystalline silica (basically microcrystalline quartz), with a variety of origins. More specifically, it looks a bit like a type of chert commonly referred to as 'porcelanite' because it has a texture resembling that of unglazed porcelain. Not sure why it has that cleavage.

[Gawdzilla Sama]

That looks like my kitchen. I tried microwaving some wet rocks recently (didn't work).

So what do I have there, and what the hell made it like that?

Looks like chert, which is a sedimentary rock composed of microcrystalline silica (basically microcrystalline quartz), with a variety of origins. More specifically, it looks a bit like a type of chert commonly referred to as 'porcelanite' because it has a texture resembling that of unglazed porcelain. Not sure why it has that cleavage.

Found it on the side of the road at the Center. I'm going to spray it with clear coat.

I'm guessing this isn't a fossil?

[Faithfree]

Chert can contain fossils, but that doesn't look like a fossil.

[Gawdzilla Sama]

Chert can contain fossils, but that doesn't look like a fossil.

Didn't think so, but I'm no expert. Anyway, it flakes nicely, lots of little cutting edges if I don't handle it nicely. There's a flint quarry at the Center, I have to get into that sucker someday.

[Faithfree]

Flint is also a variety of chert, in this case a term usually reserved for chert that forms as nodules in limestone, often with a dark grey/brown/black colour due to trapped organic carbon.

[Gawdzilla Sama]

Flint is also a variety of chert, in this case a term usually reserved for chert that forms as nodules in limestone, often with a dark grey/brown/black colour due to trapped organic carbon.

We have a shit-load of limestone around here.

[Faithfree]

Flint is also a variety of chert, in this case a term usually reserved for chert that forms as nodules in limestone, often with a dark grey/brown/black colour due to trapped organic carbon.

We have a shit-load of limestone around here.

I would hazard a guess that the chert in your photos is due to secondary silicification of limestone i.e. replacement by limestone by silica.

[Gawdzilla Sama]

Definitely "sand colored".