Three materials, named plainly on every product page.
925 sterling silver
92.5% silver, the remainder copper for strength — the standard for jewelry that has to hold a setting. Solid sterling throughout, not a plating over something cheaper. Sterling tarnishes; that is oxidation on the surface, not damage, and it polishes out. See Care.
18K gold vermeil
A thick layer of 18K gold bonded over solid sterling silver. Vermeil is a legal standard rather than a marketing word: it requires sterling underneath and a minimum gold thickness, which is why it wears far longer than ordinary gold plating over brass.
Moissanite and set stones
Lab-grown moissanite in most pieces, with cubic zirconia and lab opal used in specific designs and always named as such. Stones are prong- or channel-set by hand and checked for seating before a piece ships. More on the stone in Why Moissanite.
[TO CONFIRM]: workshop location and any hallmarking or certification you want stated here.