QUARTZITE	A compact granular rock composed of quartz crystals, usually so firmly cemented as to make the mass homogenous. The stone is generally quarried in stratified layers, the surfaces of which are unusually smooth. Its crushing and tensile strengths are extremely high; the colour range is wide.
GROUP	Metamorphic
COMMON ROCK-FORMING MINERAL GROUP	Siliceous
COMPOSITION	Quartz being the most abundant mineral with a variety of other minerals, it's the metamorphic minerals that give this stone its distinct colours and appearance.
HARDNESS	Medium to Hard.
MOHS' SCALE	4 - 7
POROSITY	0.4 - 3.9 %
ABSORPTION	0.1 - 1.4 %
WEATHERING CHARACTERISTICS	Excellent.
TENDENCIES	Absorbs oils.
COLOURS	A wide variety of colours from very light white to silver... medium to dark greys... light to dark golds... soft greens to olive green... blues, etc.
NOTATIONS	If this stone is used where oils from foods will be present, it is recommended that the stone be treated with an oil repellent. Geologically, quartzite can be part of a continuous series of stones that grade into another type of stone. The divisional boundaries can involve hundreds of feet and are not clearly distinguishable and therefore become purely arbitrary. Quartzite can grade into a Mica Schist and if a quarry is in such a transitional zone this stone commercially may be represented and sold as a quartzite. Its appearance (texture/colour) may be similar to a true quartzite, however, there will be a mineralogical deference and herein is where the weathering characteristics between these two stones defers. This transitional stone, in a wet/humid climate undergoes a mineralogical transformation that is progressive, resulting in an overall colour change to a dusty whitish colour which is irreversible. This type of stone may also develop rust spots or whole tiles may change to a reddish rusty appearance.