We strive to control the size accuracy as good as we can, therefore, you can fit our cabochons into the mold in a cost-efficient way.
In the procedure of polishing, some stones may decrease in size more than others because of the stone nature(Uneven hardness of the stone, inclusion distribution)
In general case, you may expect the sizes fall between +- 0.2mm, and rarely more than 0.25mm. From what we have measured, most of them are in exact size to +0.15mm.
What if the stones are oversized:
We would advise making the silver mold slightly larger than the stone size. For example, 12x16mm cabochon - you would make the silver mold to fit 12.1mm x 16.1mm.
There are two easy remedy solutions if you find that the stones are too large to fit:
1) Polish the inner side of the mold gently
2) Polish the stone edges gently on the side which cannot fit.
If you find any abnormal case, you are encouraged to email us, share your experience that we will immediately study with the factory and try to improve at the best we can.