Options include color, type of pieces (patio or select), thickness (¾” up to 4”), and texture (smooth, rippled, clefted, tumbled).
Patio indicates smaller diameter “stepping stone” type pieces while Select or Stand-Up indicates larger pieces. Select pieces are generally more expensive because they are harder to produce. It’s more difficult to split a large piece of stone without breaking it into smaller pieces.
Use the thinner flagstone when you have an existing subsurface like a concrete floor or a CMU block wall. Use thicker pieces when you dry-set or sand-set flagstone over dirt.