Can someone explain the Ceramics card for me? It is not clear if it gives you Pottery for free, if it lets you buy it for free, or something else. There are other cards with similar words- this answer will help me with those cards also. Thanks!

From what I understand, once you play Ceramics, you get the Pottery card for free, if it is still available.

I don't have my reference list here but isn't this the card that says something like "Pottery is now a Minor Improvement for you and costs nothing"?

If it is, that's exactly what it means. When you have an opportunity to play a Minor Improvement, you can "buy" (play) the Pottery card for free. You don't automatically get it. If you did, it would be stated.

I used that very combo myself in our game last night.