QUARTZITE IS ALSO A NATURAL STONE.  LIKE MARBLE, IT IS ALSO SEDIMENTARY AND METAMORPHIC, GIVING IT A SIMILAR LOOK TO MARBLE WHICH IS WHY MANY CONFUSE THE TWO MATERIALS.  WHERE MARBLE STARTED OUT AS LIMESTONE, QUARTZITE STARTED OUT AS SANDSTONE.  ONCE SUPERHEATED, THE SAND TURNS THE STONE INTO ONE WITH A VERY HIGH QUARTZ CONTENT, HENCE THE NAME “QUARTZITE.”  QUARTZITE IS USUALLY AN EXTREMELY HARD STONE.  SOME QUARTZITES ARE LABELED “SOFT” BECAUSE THEY ARE NOT AS HARD AS SOME OF THE OTHER QUARTZITES, BUT IT IS STILL A HARD, STRONG AND DURABLE MATERIAL.  QUARTZITE IS EXTREMELY HEAT TOLERANT, LIKE GRANITE, BUT IT DOES SCRATCH MORE EASILY THAN GRANITE, AND BECAUSE OF THE MORE SOLID APPEARANCE THE SCRATCHES SHOW MORE THAN THEY SHOW ON GRANITE.  QUARTZITE LOOKS LIKE MARBLE, BUT IS MORE RESISTANT TO STAINING AND ETCHING THAN MARBLE (ALTHOUGH IT IS MORE SUSCEPTIBLE TO STAINING AND ETCHING THAN GRANITE OR QUARTZ), MAKING IT A MORE PRACTICAL ALTERNATIVE THAN MARBLE WITH A SIMILAR LOOK BUT BETTER DURABILITY.  QUARTZITE IS POROUS AND WILL BE SEALED WITH A 10 YEAR IMPREGNATING SEALER PRIOR TO INSTALL.