Goethite is hydrated iron oxide[?], FeO(OH). Its hardness ranges from 5.0 to 5.5, and its specific gravity varies from 3.3 to 4.3. It is not generally considered very interesting as a mineral specimen; its main use is as an ironore.
... and speed of movement (it's a 3-speed stick). Gameplay is very challenging and rewarding, and once the player has gotten through a level there are bonuses ...