In mid-1885, at a mine near Freiberg, Saxony, a new mineral was discovered and named argyrodite because of its high silver content. Because of its position in his periodic table, Mendeleev called it ekasilicon (Es), and he estimated its atomic weight to be 70 (later 72). In his report on The Periodic Law of the Chemical Elements in 1869, the Russian chemist Dmitri Mendeleev predicted the existence of several unknown chemical elements, including one that would fill a gap in the carbon family, located between silicon and tin. Prediction of germanium, "?=70" (periodic table 1869) However, synthetic soluble germanium salts are nephrotoxic, and synthetic chemically reactive germanium compounds with halogens and hydrogen are irritants and toxins. Similar to silicon and aluminium, naturally-occurring germanium compounds tend to be insoluble in water and thus have little oral toxicity. Some complex organic germanium compounds are being investigated as possible pharmaceuticals, though none have yet proven successful. Germanium is not thought to be an essential element for any living organism. Germanium is considered a technology-critical element. This element forms a large number of organogermanium compounds, such as tetraethylgermanium, useful in organometallic chemistry. Germanium compounds are also used for polymerization catalysts and have most recently found use in the production of nanowires. Presently, the major end uses are fibre-optic systems, infrared optics, solar cell applications, and light-emitting diodes (LEDs). Historically, the first decade of semiconductor electronics was based entirely on germanium. Today, germanium is mined primarily from sphalerite (the primary ore of zinc), though germanium is also recovered commercially from silver, lead, and copper ores.Įlemental germanium is used as a semiconductor in transistors and various other electronic devices. Winkler named the element after his country, Germany. Although the new element somewhat resembled arsenic and antimony in appearance, the combining ratios in compounds agreed with Mendeleev's predictions for a relative of silicon. Nearly two decades later, in 1886, Clemens Winkler found the new element along with silver and sulfur, in an uncommon mineral called argyrodite. In 1869, Dmitri Mendeleev predicted its existence and some of its properties from its position on his periodic table, and called the element ekasilicon. Germanium ranks near fiftieth in relative abundance of the elements in the Earth's crust. Like silicon, germanium naturally reacts and forms complexes with oxygen in nature.īecause it seldom appears in high concentration, germanium was discovered comparatively late in the history of chemistry. Pure germanium is a semiconductor with an appearance similar to elemental silicon. It is a lustrous, hard-brittle, grayish-white metalloid in the carbon group, chemically similar to its group neighbors silicon and tin.
Braking was handled by Shimano XT disc brakes and the Mavic wheels were shod with Tioga FS100 tyres.Germanium is a chemical element with the symbol Ge and atomic number 32. RaceFace Diabolus cranks with an e.thirteen chainring and chainguide made the drivetrain strong and fuss-free, and Shimano’s DX pedals were excellent as usual. Up front was a Marzocchi 4X fork and a SRAM X-7 shifter (moving an X-9 rear mech) provided flawless gear changes, until we binned it and broke the unit. The standalone frame has the same finish as the top-end STP Zero, so we decided to build our own top-notch number with a 4X tinge. The STP frame comes with the relevant hose guides, upper and lower headset races, a seat clamp and a seatpost shim that converts the 30.9mm tube to a 27.2mm version. Short 15.75in chainstays keep acceleration ultra snappy, and a 69-degree head angle makes the ride lively without it feeling too much like a BMX.
There are two sizes available – 14 and 15in – which are essentially the same other than the 22 and 23in top tube lengths and the 4.6 and 5in head tube lengths respectively.
There are also V-brake posts and cable guides for both V-brake and hydraulic cables. The dropouts are fairly standard affairs with 135mm spacing, a tidy mech hanger and an international standard disc brake mount.
The frame is built from Giant’s ALUXX 6061 aluminium and it includes advanced features such as an ovalised down tube, an internal headset and a CNC machined chainstay yoke. The price of the STP 2 base model defies belief: it’s £299, the same as the frame alone, but has a cheaper finish. The STP is available in three builds, with even the top-of-the-range STP Zero being affordable at £650.
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