Feldspar

Feldspar is a rock forming mineral which has two other minerals present, Aluminum and Silica. Feldspar was originally found as granite pegmatite, a mineral rock. Feldspars have crystals that have come from magma in ingenous or metamorphic rocks, it is a hard mineral that rates a 6 on the Mohs scale.

Though there is another mineral which Feldspar can be mistaken for and that is Quartz. The main difference between the two minerals is the breaking down of the minerals. Feldspar breaks down in long flat surfaces, whereas Quartz does in irregular and curved shapes. To look at, Feldspar flashes in the light and Quartz glitters like Mica. And Feldspar is cloudy in appearance, whilst Quartz is clear.

Feldspar is commonly white in its colour, but have a tendency to have shades of orange and a glassy appearance. They can have other colours like grey, pink, tan and grey. The colour varieties are caused from the impurities of the crystals Therefore any mineral that's glassy and softer than Quartz is most probably a feldspar.
As feldspar is naturally found in the earth's crust in large amounts there is plenty to meet the high demand for it. It is the most common mineral on the earths crust. There are other varieties of feldspar, these include sodium oxide, potassium oxide and calcium oxide (Lime). Together these form half of the earth's crust.

Nature has created four(4) types of feldspar. They are being Albite, Barium, Amothrite and K-feldspar. When feldspar is worn from the weathers from the igenous rocks it can be found as sand, even powder like. This feldpsar powder can be used as a raw material for ceramics, Eg; ceramic glaze, glass manufacturing, porcelain and china dinnerware.

The Australian output of feldspar is of 60 000 tonnes/year and is mostly in Western Australia. Also 50 000 t/year of a quartz–feldspar blend are mined and processed for use in glass making by crushing granite close to Beechworth, Victoria.

How is it mined.
When Feldspar is mined its done from large granite amounts.
The most common procedure in mining feldspar is blasting, drilling, and drop-ball done at a quarry, dividing and fine grinding in jaw crushers, cone crushers, vibrating feeders and rod mills.

How is Feldspar processed
Two ways of processing feldspar, being crushing and grinding. The primary is to use whats called the jaw crusher first, and secondly is the impact/cone crusher.
Large parts of feldspar are fed into the jaw crusher evenly and then gradually through the vibrating feeder via a hopper for its the first phase of crushing.
After the first phase of crushing, the materials will be fed into the cone crusher via conveyor belt for second phase of crushing. The crushed feldspar is then taken to vibrating feeder for separating and grinding.
  
The most common mill for grinding feldspar is the grinding mill. This is a vertical roller mill. This is an advanced grinding machine, that can do the drying, milling, grading and transporting.
The grinding process, after having crushed the feldspar, is ground down into a powder form to the fineness required. Then collected by a cyclone collector.

What is Feldspar used for?
In today's modern industries, feldspar is quite an important mineral as it's widely used for the glass and ceramics industry. Other industries also include, soaps, fertilizer, cements and concreting, abrasives, pottery insulating products, roofing products and also as a filler for paper and textiles. Other uses of feldspar as a filler as a include; paints, rubber and plastics.

A mineral part of feldspar called Albite is an aluminum silicate. This is the ingredient which is used to form the glaze on ceramics. The alumina from the feldspar also gives a product more hardness, durability and more of a resistance to any chemical corrosion. Some ceramics would be; glazed tiles (building and bathroom tiles), porcelain and fine china and dinnerware.

When using feldspar in the glassing industry, it's an important ingredient as this is a raw material, so acts as a flauxing agent, which will help reduce the temperature of the quartz, therefore reducing the control of the viscosity of glass. In saying this the alkali in the feldspar is the flaux and lowers the glasses melting temperature and then saving monies on production costs.

The neatness that feldspar gives to a final product is assuring, as also is the stable Ph, an absent of defects, resistance to frosting, low abrasion and so adverse that there is almost an endless list for it's uses. A few more would comprise of, welding electrodes (for the production of steel), mild abrasive, latex foam, road aggregate even tableware like cuttlery.
The feldspar in tableware is greatly fusionable without any defects, leaving the end product attractive.