When was gypsum first found

The ancient Greeks used a form of gypsum in the windows of their temples because of the moonlight effect it created on the altars when the sun shone through. Benjamin Franklin was the one of the first people in the United States to use gypsum.

This land plaster is still used in agricultural applications today to provide a source of plant nutrition, to improve the structure of the soil and to reduce runoff, among other benefits. The walls and ceilings of many houses are covered with drywall because it is both easy to install and simple to finish with a coat of paint. But drywall, which is made of gypsum plaster, offers another benefit to homeowners besides ease of decorating — it offers protection in the event of a fire.

Although gypsum is not fireproof, it will protect the structure of the house from damage for a period of time. Gypsum in its natural state is an ore often found layered with limestone.

It is liberated from its natural state most commonly by surface mining. To get the gypsum ore into a state where it can be sold for its many uses, it is crushed to size using DDC-Sizers , Feeder-Breakers , Hammermill Crushers , Jaw Crushers or Roll Crushers and stockpiled to await further processing.

The crushed gypsum is screened using Vibratory Screens to separate the sizes for their different uses. One size from the screen may be sold as a cement retarder, while another size may be stockpiled for further processing. Further processing includes drying the ore to remove excess moisture, then grinding it into a fine powder known as land plaster. The land plaster is collected in a Hydrocylcone , discharged onto a conveyor and stockpiled for sale as a soil conditioner. To create stucco, the land plaster is heated with hot gasses either directly in a flash calciner or indirectly in a kettle calciner to remove much of the chemically bound water.

The stucco can be further ground and mixed with retarders to create plasters, or it can be mixed with dry additives, water, shredded paper, accelerators and soap foam; spread in a mold; and dried in a kiln to create wallboard. There is another form of gypsum which is clear and transparent, in layers like mica.

This was used, many centuries before glass was invented, as windows in the old temples. No one knows just who discovered the unique property that makes gypsum so valuable. However, some early experimenter found out that gypsum rock can be ground up to a powder and heated in a kettle calcined until most of its water content is removed.

When water is added to the resulting white powder, it forms a pliable, plastic mass Plaster of Paris which can be molded into any desired shape, after which it will harden and retain that shape. When the hardening has been completed, the substance recrystallizes and technically has then been restored to its original rock-like state.

THE ROCK NOBODY KNOWS If you were given a chance to win a jackpot by correctly naming a material that was used in the pyramids and in your toothpaste; that helps peanuts grow and makes movie snow; and that is used in mushroom beds and the walls of your house, chances are at least to 1 that the quizmaster would holler "Sorry, your time is up," before you could say "hydrous calcium sulphate. When that happens, the rock becomes a fine powder, commonly known as Plaster of Paris.

By returning the water to the powder, one can make a pliable mortar that can be formed into any shape and hardened. Gypsum is the only natural substance that can be restored to its original rock-like state by the addition of water alone. How well it has served us through the centuries can be seen from a listing of a few of the ways in which you come in contact with gypsum during an average day.

Most of the fixtures in your bathroom were made of clay formed in a mold of gypsum plaster and chances are that the tile on the wall is set in another type of plaster. At the breakfast table, you use plates, cups, and saucers which were shaped on or in a gypsum mold. So were the sterling silver handles of your knives, forks, and spoons. When you settle back after breakfast for a second cup of coffee, you light your cigarette with a match which has gypsum in its head. Of course, the walls and ceilings in your home almost certainly are made of gypsum lath and plaster or gypsum wallboard.

When you leave home for work you step on sidewalks made of Portland Cement which contains gypsum to regulate the setting time. Maybe your walk is covered with chalk marks from the game the children were playing the night before.

Many of the streets and highways you travel daily also contain gypsum. Your car windows are made of plate glass which was held in a bed of gypsum during the polishing process. Many of the small metal gears, the instrument bases and other metal parts on your car were cast in gypsum molds by a process that was largely perfected during World War II. Your doctor uses gypsum when he builds splints for broken limbs from a gauze impregnated with orthopedic plaster.

Everybody uses the rock nobody knows. Benjamin Franklin, the great experimenter, was one of the first to introduce it in this country when he used ground raw gypsum, called land plaster, on his farm. Today, , tons of land plaster are used in the United States each year see ad below. Hollywood uses gypsum to represent snow. Whether for a white Christmas or a raging blizzard. Most of the spectacular movie and TV sets, too, are formed from gypsum plaster. At the end of the glamour scale, gypsum is mixed with manure used to make mushroom beds.

By far the largest part of the gypsum used in this country goes into wallboard and lath for our homes. These gypsum "boards" are formed by sandwiching a core of wet plaster between two sheets of heavy paper. When the core sets and dries out, the sandwich becomes a strong, rigid, fireproof building material. Manufactured in unbelievable quantities on continuous machines almost a quarter mile in length, gypsum wallboard and lath, are among the most important materials used in housing.

Drywall is composed of about a quarter inch of gypsum between two sheets of paper "lath". Gypsum has been found in:. In , the American Augustine Sackett invented a machine for producing plasterboard - also known as gypsum board, wallboard, and drywall - from layers of paper and gypsum. The first plasterboard plant was built in the USA in In , plasterboard manufacturing was improved by the American Stephen Kelly. He patented a gypsum core with a layer of paper on each side.

Modern plasterboard was born. In Europe, the first modern gypsum plasterboard plant was built in the UK in Liverpool in and the second in London in In continental Europe, Latvia had the first factory, in Riga in