Chalky white stones

Dear Andreas,

I have not found much information about pancreatic stones but somewhere in the Net I read that they can be chalky white. Recently I have passed 2 COMPLETELY WHITE stones and 1 with brownish surface but white inside. All the 3 were semi-hard and quite dry with chalky solidity (different solidity from the typical green stones, which are more mushy). Are these chalky stones, pancreatic stones?

Thank you very much.

PTtogether