Not sure from your descriptions but I think you missed the Skey with concentric circles.

BTW, did you know the distributor of the Skey mold B.C. Wills, and the manfacturer the Burt Co, called the mold GEM? The Lkey was called Super Gem.

There were a number of Skey molds made over the years. I have a Burt list (somewhere) that shows the dates each new mold was made.