I work mainly in base metal clays, which fire hotter than silver and I've used several of these now, as well as smaller sizes and they have come out flawlessly even over 800°C. No clouding or change of colour. I just make sure to clean the table of the gemstone last thing before firing, in case any metal clay powder has stuck to finger prints, as this can spoil the sparkle. These mixed packs represent very good value.

These are really lovely and such a good mix

Really pleased with these. Haven't used them yet but plans are forming. Can't wait to have a go.