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Cally Oldershaw is a gemologist and science educator. She is the author of several very widely held books about gems. Oldershaw is Liaison Officer for the Geological Society of London and an examiner for the Gemmological Association of Great Britain. [1]
She also wrote the multiple parts of the Geological society of London series of booklets, Earth in our Hands, [5] and many parts of the Series: Closer look at... series for children published by Copper Beech Books.
Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The atoms are linked in a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of SiO2. Quartz is, therefore, classified structurally as a framework silicate mineral and compositionally as an oxide mineral. Quartz is the second most abundant mineral in Earth's continental crust, behind feldspar.
Garnets are a group of silicate minerals that have been used since the Bronze Age as gemstones and abrasives.
Lapis lazuli, or lapis for short, is a deep-blue metamorphic rock used as a semi-precious stone that has been prized since antiquity for its intense color. Originating from the Persian word lazhuward meaning 'blue', lapis lazuli is a rock composed primarily of the minerals lazurite, pyrite and calcite. As early as the 7th millennium BC, lapis lazuli was mined in the Sar-i Sang mines, in Shortugai, and in other mines in Badakhshan province in modern northeast Afghanistan. Lapis lazuli artifacts, dated to 7570 BC, have been found at Bhirrana, which is the oldest site of Indus Valley civilisation. Lapis was highly valued by the Indus Valley Civilisation. Lapis beads have been found at Neolithic burials in Mehrgarh, the Caucasus, and as far away as Mauritania. It was used in the funeral mask of Tutankhamun.
Onyx is the parallel-banded variety of chalcedony, an oxide mineral. Agate and onyx are both varieties of layered chalcedony that differ only in the form of the bands; agate has curved bands while onyx has parallel bands. The colors of its bands range from black to almost every color. Specimens of onyx commonly contain bands of black and/or white. Onyx, as a descriptive term, has also been applied to parallel-banded varieties of alabaster, marble, calcite, obsidian, and opal, and misleadingly to materials with contorted banding, such as "cave onyx" and "Mexican onyx".
Anglesite is a lead sulfate mineral with the chemical formula PbSO4. It occurs as an oxidation product of primary lead sulfide ore, galena. Anglesite occurs as prismatic orthorhombic crystals and earthy masses, and is isomorphous with barite and celestine. It contains 74% of lead by mass and therefore has a high specific gravity of 6.3. Anglesite's color is white or gray with pale yellow streaks. It may be dark gray if impure.
Hutchinson was a British publishing firm which operated from 1887 until 1985, when it underwent several mergers. It is currently an imprint which is ultimately owned by Bertelsmann, the German publishing conglomerate.
Phenakite or phenacite is a fairly rare nesosilicate mineral consisting of beryllium orthosilicate, Be2SiO4. Occasionally used as a gemstone, phenakite occurs as isolated crystals, which are rhombohedral with parallel-faced hemihedrism, and are either lenticular or prismatic in habit: the lenticular habit is determined by the development of faces of several obtuse rhombohedra and the absence of prism faces. There is no cleavage, and the fracture is conchoidal. The Mohs hardness is high, being 7.5–8; the specific gravity is 2.96. The crystals are sometimes perfectly colorless and transparent, but more often they are greyish or yellowish and only translucent; occasionally they are pale rose-red. In general appearance the mineral is not unlike quartz, for which indeed it has been mistaken. Its name comes from Ancient Greek: φέναξ, romanized: phénax, meaning "deceiver" due to its close visual similarity to quartz, named by Nils Gustaf Nordenskiöld in 1833.
The Kokcha River is located in northeastern Afghanistan. A tributary of the Panj river, it flows through Badakhshan Province in the Hindu Kush. It is named after the Koksha Valley. The city of Feyzabad lies along the Kokcha. Near the village of Artin Jelow there is a bridge over the river.
Batsford Books is an independent British book publisher.
Dunedin Academic Press Ltd (Dunedin) is a small independent academic publisher in Edinburgh, Scotland which publishes mainly books for the tertiary (undergraduate) level and periodically for postgraduate/research audiences. It has a London office as well. Dunedin also publishes books appealing to non-specialist adults interested in learning more about geology. Graham Park's Introducing Geology, now in its Second Edition, is a notable example. Dunedin's Introducing Earth and Environmental Sciences series, of which Introducing Geology was the first title now contains books covering topics in Astronomy, Meteorology and Oceanography as well as a lengthening list of geology and other earth science topics. "The Abyss of Time" by Paul Lyle won the Association for Science Education Book of the Year award in 2017.
Donkey Punch is a crime novel by Scottish author Ray Banks. It was first published in the United Kingdom by Edinburgh-based company Birlinn Ltd in 2007, and again by the same publisher in 2008. In the United States it was published by Houghton Mifflin Harcourt in 2009, titled Sucker Punch, and was reprinted in 2011.
Ernest Benn Limited was a British publishing house.
Frederick George "Derick" Emmison was a British archivist, author and historian. He was County Archivist for Bedfordshire between 1925 and 1938, County Archivist for Essex between 1938 and 1969, a founder member of the British Records Association and the Society of Archivists, and a winner of the John Bickersteth Medal in 1974 and the Medlicott Medal in 1987. He was also a prolific author who made a significant contribution to our understanding of the Elizabethan era through close analysis of the minutiae of local records of that age in Essex.
Rubellite is the red or pink variety of tourmaline and is a member of elbaite. Rubellite is also the rarest gem in its family. It is occasionally mistaken for ruby. These gems typically contain inclusions.
Azurmalachite is a mixture of azurite and malachite. It is alternatively called azuromalachite, azurite-malachite and malachite-azurite.
Goshenite is a colorless gem variety of beryl. It is called the mother of all gemstones because it can be transformed into other like emerald, morganite, or bixbite. Goshenite is also referred to as the purest form of beryl since there are generally no other elements present in the stone. The gem is used as imitation for diamond or emerald by adding colored foil on it.
Morganite is an orange or pink variety of beryl and is also a gemstone. Morganite is mined in Brazil, Afghanistan, Mozambique, Namibia, the United States, and Madagascar.
Red beryl, formerly known as bixbite and marketed as red emerald or scarlet emerald, is an extremely rare variety of beryl as well as one of the rarest minerals on Earth. The gem gets its red color from manganese ions embedded inside of beryllium aluminium cyclosilicate crystals. The color of red beryl is stable up to 1,000 °C (1,830 °F). Red beryl can come in various tints like strawberry, bright ruby, cherry, and orange.
Aquamarine is a pale-blue to light-green variety of beryl. The color of aquamarine can be changed by heat.