Synthesised Platinum Sceptre

Hello, I'm new to the game and I dropped this item, but I can't find it anywhere, can anyone explain to me what the synthesised part means please?

Synthesised items have a random Implicit mod (the 10% increased critical strike chance) which replaces the default implicit mod. Some of these mods can be insanely powerful, for example +1 charges on a ring or +% attributes, Cast X curse on hit jewellery etc. This item is worthless.