Colorado Yule Marble is a marble of metamorphosed limestone found only in the Yule Creek Valley, in the West Elk Mountains of Colorado, 2.8 miles southeast of the town of Marble, Colorado. Wikipedia
Yule Marble, also known as Calacatta Colorado, has been used in many famous buildings and monuments in the United States and around the world, including the Lincoln Memorial, Washington Monument, Hearst Castle, Tomb of the Unknown Soldier, and numerous capital buildings, banks, and hotels.
Yule marble was designated the official state rock of Colorado in 2004 after Girl Scout Troop 357 of Lakewood petitioned the Legislature.
Marble is found in many parts of the world. In the United States, the major marble-producing areas are found in Alabama, Colorado, Montana, Tennessee, Texas, and Vermont.
Soapstone (also known as steatite or soaprock) is a talc-schist, which is a type of metamorphic rock. It is largely composed of the mineral talc, thus is rich in magnesium. Wikipedia
Soapstone is typically gray, bluish, green, or brown in color, often variegated. It has varying amounts of other minerals besides talc such as micas, chlorite, amphiboles, pyroxenes, and carbonates. It is a soft, dense, heat-resistant rock that has a high specific heat capacity. geology.com
Much of the soapstone seen these days comes from Brazil, China or India. Significant deposits also exist in Australia and Canada, as well as in England, Austria, France, Italy, Switzerland, Germany, and the United States. sciencing.com
Choosing a stone to carve is based upon the hardness of the stone. Soapstone is the softest of carving stones, followed by alabaster; marble and granite are the hardest and typically carved by professionals. Within each type of carving stone, there are varying degrees of hardness.
Limestone is a sedimentary rock that is formed chiefly by an accumulation of organic remains (such as shells or coral), composed mainly of skeletal fragments of marine organisms such as coral, forams, andmollusks. Its major materials are the minerals calcite and aragonite, which are different crystal forms of calcium carbonate. About 10% of sedimentary rocks are limestones. Wikipedia
Today Earth has many limestone-forming environments. Most of them are found in shallow water areas between 30 degrees north latitude and 30 degrees south latitude. Limestone is forming in the Caribbean Sea, Indian Ocean, Persian Gulf, Gulf of Mexico, around Pacific Ocean islands, and within the Indonesian archipelago. Limestone is most often mined from a quarry. However, underground limestone mines are found at places in the central and eastern United States, especially in and near cities. Geology.com
Frances A Listou
Alabaster is a mineral or rock that is soft, often used for carving, and is processed for plaster powder. Geologists define alabaster only as the gypsum type. Chemically, gypsum is a hydrous sulfate of calcium, while calcite is a carbonate of calcium. Wikipedia
The root of alabaster is a Greek word meaning "perfume vase," alabastros.
Talc is a metamorphic mineral that results from the metamorphism of magnesian minerals such as serpentine, pyroxene, amphibole, and olivine, in the presence of carbon dioxide and water. This is known as "talc carbonation" or "steatization" and produces a suite of rocks known as talc carbonates. Soapstone is a metamorphic rock composed predominantly of talc. Wikipedia
Most of the talc deposits in the United States are in metamorphic rocks on the eastern side of the Appalachian Mountains and in rocks metamorphosed in convergent terranes of Washington, Idaho, Montana, California, Nevada, and New Mexico. Deposits of talc are also found in Texas. Geology.com
Talc is usually green, white, gray, brown, or colorless. It is a translucent mineral with a pearly luster. It is the softest known mineral and is assigned a hardness of 1 on the Mohs Hardness Scale.