Ceramic itself does not leach minerals, Dooms. The problem is with ceramic pots that have been used to grow conventional plants; if the ceramic is porous and unglazed, it can absorb minerals from the conventional potting mix, and these are what leach back out and harm CPs. It's not the pot's fault - it's what was grown in it before that matters. A brand new ceramic pot is totally fine. You can also treat used pots with white vinegar to dissolve any salts they've absorbed.
~Joe