The jewelry we sell has been hand fabricated or handcast. We use natural gemstones and predominantly work with high karat gold (22k), sterling silver or fine (pure) silver. Lower karat gold is used for strength when necessary (our ring shanks are mostly 20k or 18k gold for this reason. ) We sometimes like to experiment with new materials such as Argentium (low tarnish) silver, "reactive" metals like titanium or niobium, or bonded metals. We will always tell you what materials we have used in our jewelry, and are happy to work with you on a particular request.