The Microcrystalline Hard wax is, as the name suggests, harder than the former and has a higher melting point (170°F to 180°F). The latter feature is interesting in many cases. You'll use it for instance to make the shell of a Hurricane candle or to overdip pillars and tapers to give them a better burning behaviour and prevent them from dripping. Dipping candles into micro hard wax at a specific temperature will give the candles a great snowflake effect. Used to strengthen wax. Use 1 - 2%.