Pewter wine coasters from Crest Silver Mfg. Co. 'Delft'- These do not have a leather or glass bottom, they have a pewter bottom with a chain of flowers encompassing a smaller circle.

I picked these guys up today, and thought that I would be able to find the worth no problem searching through various sites.  I have found nothing close really... They seem to be wine coasters, and they say Delft by Crest Silver Mfg Co. Matawan, NJ.  The Bottom is slightly raised with a circle of pewter dots around the bottom.  The actual wine coaster looks like those with the leather bottom.  However the bottom of the coaster has a small circle of the dots in the middle, and that is surrounded by four groups of flowers also in a circle. 

Here is a photo I have let me know if you need anything further.

Thanks!