These are what I assume to be promotional advertising coasters produced by Claudius Ash, the dental equipment company, to promote their impression tray compound.
I am not an expert but I assume that they are made of the actual compound itself to show the degree of detail that can be captured when taking an impression.
On one side it says around the perimeter Ash's Impression Tray Compound, Manufactured in England. In the centre are the letters C A & S on top of an Ash leaf, I assume this stands for Claudius Ash & Sons. On the reverse is a pattern of interlocking circles, very similar to the patterns seen on old machine turned silver items. The material has taken up some very fine detail. They are 84mm in diameter and 4mm thick.
The coasters are in good condition, although there is some chipping around the edges. The material does seem very brittle.
I have no idea how old they are but the Ash's logo may give a clue.
Please note. I do my best to accurately photograph and describe the condition of the items for sale, including any minor defects, but all pieces are vintage and have had previous lives and so may have minor flaws.
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