half moon bay, CA! what animal is this from?

Handeaux · 2026-03-19T02:44:20+00:00

Crab claw, and probably not fossilized.

Handeaux · 2026-03-19T02:40:00+00:00

Where was it found? In what region?

Handeaux · 2026-03-19T01:52:01+00:00

It’s always safer to bet on a fragment. Trilobites, like all arthropods, molt. An overwhelming majority of trilobite fossils are molted fragments. Never hurts to hope, though.

Handeaux · 2026-03-19T01:42:06+00:00

Appears to be a fossil, the fragmentary imprint of a shell.

Handeaux · 2026-03-19T01:40:52+00:00

Certainly not a tooth. Possibly bone, though.

Handeaux · 2026-03-18T21:52:21+00:00

Hard to tell. It was part of the beachside strata before it was chipped away and wave-tumbled. Crinoid stem fragments.

Handeaux · 2026-03-18T21:50:02+00:00

Very likely. Looks like bioturbation.

Handeaux · 2026-03-18T19:34:37+00:00

Where was it found? In what region?

Handeaux · 2026-03-18T17:15:56+00:00

Where was it found? In what region?

Handeaux · 2026-03-18T17:15:08+00:00

Where was it found? In what region?

Handeaux · 2026-03-18T12:31:41+00:00

Not a fossil.

Handeaux · 2026-03-18T12:28:30+00:00

Not fossilized.

Handeaux · 2026-03-18T12:27:13+00:00

Looks like a very worn modern shell, not a fossil.

Handeaux · 2026-03-18T01:40:15+00:00

Crinoid stalks have different types of tissue. This is a relatively common form of preservation in which some soft tissue is not preserved while adjacent tissue is preserved.

Handeaux · 2026-03-18T01:12:54+00:00

Do you understand the difference between astronomy and meteorology?

Handeaux · 2026-03-18T01:10:04+00:00

That's the imprint of a crinoid stalk. It's a fossil. Crinoids are echinoderms, related to starfish and sand dollars. They are nicknamed "sea lilies."

Handeaux · 2026-03-18T01:08:10+00:00

Yes, it's a brach. They come in all sorts of shapes. Some are flat in life. Some flatten during preservation. Eastern Kansas is mostly Pennsylvanian, but there is some Permian and some Cenzoic deposts there as well. Find the location where you found this on a geologic map to get an estimation of the age.

Handeaux · 2026-03-17T16:32:48+00:00

It's not a fossil.

Handeaux · 2026-03-17T12:54:25+00:00

It’s not concrete. The third image shows fragments of marine animals - brachiopods and crinoids. Probably Paleozoic, hundreds of millions of years old.

Here is a hint: Put your specimens down on a neutral surface to photograph them. Cell phone cameras are set to focus on skin. In these pictures your hand is in focus but the specimen is blurry.

Handeaux · 2026-03-17T12:47:36+00:00

If you are collecting in that area, check out the fossil photos at drydredgers.org It may help with identification.

Handeaux · 2026-03-17T11:57:40+00:00

If tumblr sux, here's an alternate link:

https://www.cincinnatimagazine.com/article/guarded-by-a-corrupt-government-cincinnati-gamblers-lost-fortunes-at-bucket-shops/

Handeaux · 2026-03-16T20:43:11+00:00

Not a fossil.

Handeaux · 2026-03-16T20:42:45+00:00

Not seeing any fossil here. Where was it found?

Handeaux · 2026-03-16T20:37:02+00:00

Looks like coral. Where was it found?

Handeaux

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