The machines that slice almonds are a little out of the league of the home kitchen. Even by hand, it is not practical to slice almonds yourself.

In commercial production, whole almonds are heated to around 160°F (71°C) and "conditioned with moisture," at which point they become soft enough to feed through the slicing machine without shattering.

No mandolin or home slicer does fine enough work to handle teensy-tinsey little almonds. You could blanch your whole almonds and have at them with a paring knife, but we bet by the fourth almond you'd find yourself in the car, halfway down the block toward the grocery store, without even realizing you'd left the kitchen.