What kind of rocks are these?

Some of the holes are actually formed during a lava flow as part of the pyroclastic process. Because they cooled relatively quickly, the holes are formed from releases of CO2 in most cases, but also other dissolved gasses and water.
 
Except Texas holey rock itself doesn't come from the beaches of Cali ;)


Pap, next time I see you in chat, I'm punching you in the bio balls.


:frog::thud:
 
Many holes in beach rocks are formed by bivalves secreting acid into them to make little bivalve houses.

Yeah, there are little remainders of old inhabitants left in these rocks, I see some crusty hermit crab legs in one hole and tiny little shells in others. If I get the green light on using them in a tank I'll definitely have to give them a good boil and scrub.
 
cool rocks! Wish i had some of those!
 
cool rocks! Wish i had some of those!


I'm going back tomorrow so I'll collect more, and if I get some interesting looking ones ill put them up for trade or something :)
 
$100 says that they fail the fizz test. But since they're going in with Africans it doesn't matter.
 
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