Is this a fossil? Bone? Tooth?

[Julieway]

Hi, I found this on the beach in Northern California and am just curious to know what it is. I can't tell if it's just a shell or bone or if it's actually a fossil. Just thought it would be fun to find out. Thank you!

[ynot]

Welcome to TFF!

That is a piece of a barnacle shell.

Does not look fossilized.

Tony

[Harry Pristis]

 

This reminds me of a segment of barnacle (Balanus).

[Julieway]

Thank you. Much appreciated.

[doushantuo]

Both bone and cirriped crustacean plates contain the phosphate mineral dahllite,so there is similarity between barnacle plates and vertebrate bone

 

[Vieira]

A barnacle fragment with any doubt.

 

Looks like modern.

[abyssunder]

I agree. More details regarding to barnacle morphology, here :

 

BENNY K.K. CHAN et al. 2009. CRUSTACEAN FAUNA OF TAIWAN: BARNACLES, VOLUME I – CIRRIPEDIA: THORACICA EXCLUDING THE PYRGOMATIDAE AND ACASTINAE.

 

Sangeetha Raman, Ravi Kumar. Construction and nanomechanical properties of the exoskeleton of the barnacle, Amphibalanus reticulatus. Journal of Structural Biology 176 (2011) 360–369.