It's been a while I am trying to ID this rock. First, I thought it was an instantly cristallized tentacle or something like this, because the circles are in perfect rows. 4 rows of double circles are visible, and then, it's like it continues, but it's squeezed. Many forums said it's impossible that a tentacle got fossilized this well... If it's not a fossil, maybe a strange rock, agate, jasper ? It was found on a beach at Perce, Gaspesie, Qc, Canada. Please help me with this !!!
In the picture with 3 objects, is the first one a fossilized Tabulate Coral ? (also found at the same place)
I think the orangey one might be an encrusting alga. Here's an example (I'm not saying this is your one) - http://intertidal-novascotia.blogspot.com/2012/05/clathromorphum-spp-coralline-crust.html
It looks like it has been worn and polished somewhat by wave action.
I'm not sure about the other two.
if it's what you think, I'm wondering why it preserved it's colours. If it's algae, so it's a fossil. You dont have any idea of the reddish layer ? The pattern of circles (not fully visible on my photos) goes like this :
o o o o
o o o o
If it's another algae, how come it got crystallized ? ( what's around it is a partially transparent mineral )
How old could this be ?
I am sure it is not fossil; it is modern, a few years old. But it is encrusting a pebble of rock that it probably millions of years old. Modern encrusting algae are hard and come in a range of colours (pink more common than red).
The pattern of ovals and lines: I am sure these are the result of growth layers being eroded. Encrusting algae often have protuberances; if they get worn down, they will become oval shapes. And if they are comprised of layers, the ovals will contain smaller ovals. The lines also represent layers, and may have formed at the edge of the encrustation, perhaps where the pebble met the sand in which it was half-buried.
More on coralline algae
List of coralline algae species in the British Isles
Please note: coralline algae is still just a suggestion.
We could really do with an aquatic zoologist...