Fibrous or splintery are other fracture options. Hardness will be expressed as a number derived from the Moh's Hardness Scale. How to determine the number when testing your minerals is explained in most books on minerals. Magnetism refers to whether the mineral is attracted by a magnet. Some samples might themselves be magnetic.
Crystal refers to the shape of the crystals that make up the mineral.
Specific Gravity equals the mass of the mineral sample in the air divided by the mass of an equal volume of water. This will be expressed as a number. Fluorescent refers as to whether a mineral glows under ultraviolet light. Phosphorescent minerals will continue to glow after the ultraviolet light is turned off. Double Refraction refers to a situation in which the mineral splits light passing through it into two paths.