High-paying symbols, often called premiums, are the regular symbols that pay most for a winning combination. They are usually themed artwork such as characters, animals or treasures, while lower values use card ranks or gems.
They pay more because they land less often. Reel strips carry fewer of them, and the paytable prices them accordingly. A typical paytable lists four or five premiums above a set of low-paying symbols, with the top premium paying the most for five of a kind.
Many features work by producing more premiums than usual: symbol upgrades turn low symbols into high ones, and some free spins rounds remove low symbols from the reels altogether. The wild often doubles as the top-paying symbol in its own right.
The actual values vary by game and are shown in each game's paytable, scaled to your stake.