WorldWide Drilling Resource

Calcite is one of the most common minerals. It occurs in a variety of shapes and colors, making up a major portion of many of the earth's rocks. Calcite is a mineral component of limestone, which is used primarily as construction aggregates, as well as in production of lime and cement. It is used in a variety of commercial applications including road construction, riprap and jetty stone, railroad ballast, poultry grit, mineral food, sugar processing, flux stone in steel produc- tion, sulfur dioxide removal in power plants, coal mine dusting to prevent explosions, acid water treatment, and asphalt fillers. Many important chemicals are created from calcite, as well as useful drugs. It is also crucial in the manufacture of fertilizers, metals, glass, rubber, and paint. It is the main component of chalk, and forms rocks which are used for ornamental purposes, such as marble and banded travertine or tufa. The transparent Iceland Spar variety was used as prisms for polarizing microscopes and other optical devices, and possibly the viking sunstone used for navigation purposes. Copper in its native form was probably one of the early metals worked by ancient people. Nuggets of the metal could be found in streams in a few areas, and the mineral’s properties allowed it to be easily worked without a required processing step. Ancient civilizations used it for ornaments. Native copper is found only in small quantities throughout the world, but there are a few areas which are rich in findings. Native copper was the only source of copper until recent times, when extraction methods were improved. Copper ores are more abundant than native copper, and are the main source of copper today. The mineral ranks second as the most-used metal in the world. Its popularity is garnered from its special properties of conduc- tivity, malleability, resistance, and beauty. The main uses of copper are electrical. The mineral is very ductile and can be drawn into very thin wires, which serves as its primary electrical function. It is used for electrical machinery such as motors, electromagnets, generators, and commu- nication devices. It has been fashioned into ornamental objects and cooking uten- sils since the beginning of mankind, and has been used in pigments, insecticides, and fungicides, although it has lately been replaced by synthetic chemicals. Coins have been made of copper throughout history. U.S. pennies were made out of copper until 1982, when the cost of copper exceeded the value of the penny. Pennies are now made from zinc and plated with copper. The World of Minerals Native Copper. 41 WorldWide Drilling Resource ® FEBRUARY 2018