There are two types of gems. Skill gems and support gems. You'll probably get your first support gem around level 10 from a quest reward. In Path of Exile, many items contain colored gem sockets. Skill gems of the matching color may. an item to increase the chances of rolling more sockets/links. Added new currency item - Orb of Fusing: Rerolls socket links on an item.
One can also sell Clarissa an Orb of Fusing in exchange for one Orb of Chance Orb of Chance Stack Size: Someone thought it was funny to bring back a topic that's been dead for 3 years. To add to what Mayfil said, did you know you can find items with sockets of 3 colors directly from vendors, and sell them back directly to them for a chroma? You don't want to gamble on fusing. All you need to know about currency is:
Poe gem slots - behält