Definition of COMMODITY RATE. : a common carrier rate distinguished from a class rate and applicable only to a specific commodity or group of related commodities carried between specific points or territories. ADVERTISEMENT. a common carrier rate distinguished from a class rate and applicable only to a specific commodity or group of related commodities carried between specific points or territories.
Cubic Zirconia. Cubic zirconia (CZ), a diamond simulant, is not only the oldest diamond substitute, but also the most popular. Composed of zirconium oxide (ZrO 2) the mineral is extremely rare in natural form. Discovered by German mineralogists in 1937, zirconium wasnât considered economically feasible.ubic zirconia possesses less brilliance (less sparkle), but has more fire (flashes of rainbow color.) CZ is also very hard, not quite as hard as a diamond, but like a diamond can scratch glass.
The most ancient samples come from an area in Western Australia known as Jack Hills, where they are embedded in sandstone deposits. Advertisement To extract the zircons from the sandstone, scientists use a hammer to break the rock into chunks about 5 inches across. Then they grind the chunks into a wet sand. The sand goes into a toxic solution that is so dense, only zircon and other very heavy materials sink to the bottom.