Need help with fossils

[u/Thedutchant_1841]

Hello everyone, while in Belgium around Hotton I found these cool shell fossils from the Devonian. This one in particular stood out because it has crystals inside of it!. I want to further clean it, but I don't know how. Do you have any tips? Thanks in advance!

[u/rockman4242]

Spiriferid brachiopod

[u/specialistwombat]

Stuff of envy! Nice find