what kind of rock is this?

[eruyanik]

i found it on the sea shore and it looks kind of sea thing i don't know say sponge, mollusk, crustaceans or both of them.

what we should call this one? which type it is? what kind of minerals in there?

 

Amazon Forum Fav 👍

A Handbook of Civil War Bullets and Cartridges - Grab it through Amazon!

[IAMZIM]

That is unusual looking! The lines I'm seeing make me think it could be a jasper with fortification, like an agate can have, the grey section look granitic, and the rusty looking elliptical parts look like iron type inclusions of hematite or some other iron mineral. I'm not confident on any of those assessments however.... I would have definitely picked that up though!

 

[eruyanik]

That is unusual looking! The lines I'm seeing make me think it could be a jasper with fortification, like an agate can have, the grey section look granitic, and the rusty looking elliptical parts look like iron type inclusions of hematite or some other iron mineral. I'm not confident on any of those assessments however.... I would have definitely picked that up though!

thank you for the precious evaluation as for me Jason!

very much appreciated, with my best regards

Ersin

 

[stdenis_jd]

this one is interesting, I'm with Zim as far as not being sure although from the looks I would say the same thing. A few things would be helpful:

hardness test (matrix/white area)
acid test (HCl will show a violent reaction, white vinegar will be slow and small bubbles but it will happen eventually if positive)
see if you can break off a small chunk so we can see a fresh surface. That would help understand this matrix - it has been tumbled and weathered by waves so the surface is obscured

:edit: the striations are interesting, kind of indicates marble/limestone...should react to acid if it is

 

[eruyanik]

ok, i will give it a try you said testing with vinegar takes time, and it's a good point to me. because i have tried it before and expected a fast response and non i had seen

 

[stdenis_jd]

Yeah u might have to wait two three minutes or so and you should see tiny bubbles if it is calciferous. It will effervesce so you'll see bubbles rising from the rock through the solution instead of simply trapped air