Primary gold

Gold

Gold is a chemical element with the symbol Au and an atomic number of 79. Gold is a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. Chemically, gold is a...

 typically occurs in quartz

Quartz

Quartz is the second-most-abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. There are many different varieties of quartz,...

 veins

Vein (geology)

In geology, a vein is a distinct sheetlike body of crystallized minerals within a rock. Veins form when mineral constituents carried by an aqueous solution within the rock mass are deposited through precipitation...

. The extraction of gold ore

Ore

An ore is a type of rock that contains minerals with important elements including metals. The ores are extracted through mining; these are then refined to extract the valuable element....

 from these hard quartz veins was historically referred to as quartz reef mining.

A Prussia

Prussia

Prussia was a German kingdom and historic state originating out of the Duchy of Prussia and the Margraviate of Brandenburg. For centuries, the House of Hohenzollern ruled Prussia, successfully expanding its size by way of an unusually well-organized and effective army. Prussia shaped the history...

n engineer

Engineer

An engineer is a professional practitioner of engineering, concerned with applying scientific knowledge, mathematics and ingenuity to develop solutions for technical problems. Engineers design materials, structures, machines and systems while considering the limitations imposed by practicality,...

, Jacob Brache was the first to think that quartz reefs might have even more gold than alluvial fields.

The new mining

Mining

Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...

 companies had to sink very deep shafts to get quartz from the reefs deep underground. Horizontal tunnels called drives were dug out from the shaft at different levels to find the gold-bearing rock

Rock (geology)

In geology, rock or stone is a naturally occurring solid aggregate of minerals and/or mineraloids.The Earth's outer solid layer, the lithosphere, is made of rock. In general rocks are of three types, namely, igneous, sedimentary, and metamorphic...

.

All rock dug out had to be hoisted to the surface. So did lots of water

Water

Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...

 and even the workers at the end of the day. Big engine

Engine

An engine or motor is a machine designed to convert energy into useful mechanical motion. Heat engines, including internal combustion engines and external combustion engines burn a fuel to create heat which is then used to create motion...

s were installed to hoist lifts and buckets up the shafts.

On the surface above the shaft stands a building known as the poppet head or pit head. The poppet head contained a wheel called a gin wheel which lifted buckets of rock up to a raised platform called a Brace. Wheeled buckets then carried the rock along elevated tracks to waste dumps or processing works. The steel

Steel

Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...

 cable that hoisted the bucket passed over the gin wheel.

The gold was brought to the surface as small particles embedded in lumps of quartz. The quartz was then crushed into a fine dust by stamping batteries in a stamping mill. A stamping battery contained a row of stampers. On the bottom of each stamper was a heavy piece of steel. Each stamper was connected to the cam shaft which was turned by a water wheel

Water wheel

A water wheel is a machine for converting the energy of free-flowing or falling water into useful forms of power. A water wheel consists of a large wooden or metal wheel, with a number of blades or buckets arranged on the outside rim forming the driving surface...

. The steel shoes went up and down between wooden guides and pounded the quartz which had been fed into steel boxes underneath the stampers. Ideally the stamping batteries would work 24 hours a day.

After crushing, the quartz dust was mixed with water to make sloppy mud

Mud

Mud is a mixture of water and some combination of soil, silt, and clay. Ancient mud deposits harden over geological time to form sedimentary rock such as shale or mudstone . When geological deposits of mud are formed in estuaries the resultant layers are termed bay muds...

 which then ran down sloping tables, called concentrating tables. On top of these tables were copper

Copper

Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...

 sheets coated with mercury

Mercury (element)

Mercury is a chemical element with the symbol Hg and atomic number 80. It is also known as quicksilver or hydrargyrum...

, which attracts gold. The gold particles stuck to the mercury, and could be collected from there.

Quartz mines

• Victoria Quartz mine, Bendigo: In Australia
  Australia
  Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
  
  , the deepest shaft used to mine a quartz reef was almost a kilometre and a half deep.
• Central Deborah gold mine, Bendigo: The mine still stands today. It started mining in 1851 and was mined continuously for 157 years. It was a deep reef quartz goldmine. During the working life of the mine 60,000 tonne
  Tonne
  The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...
  
  s of quartz was brought to the surface but only 1 tonne of gold extracted.
• Gold Hill (Nevada County, California)
  Gold Hill (Nevada County, California)
  Gold Hill, in Grass Valley, California, was the site of one of the first discoveries of quartz gold in California. While quartz gold was also found in other areas of Nevada County, California during the same time, it is this find near Wolf Creek that led to quartz-mining frenzy and subsequent...
  
  , USA: Site of one of the first discoveries of quartz gold in California, and now California Historical Landmark
  California Historical Landmark
  California Historical Landmarks are buildings, structures, sites, or places in the state of California that have been determined to have statewide historical significance by meeting at least one of the criteria listed below:...
  
  No. 297: "...this discovery created the great excitement that started the development of quartz mining into a great industry."