Rocks
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Laterite
Laterite is a soil type rich in iron and aluminium and is commonly considered to have formed in hot and wet tropical areas. Nearly all laterites are of rusty-red coloration, because of high iron oxide content. They… Read more.
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Saprolite
Saprolite is a chemically weathered rock. Saprolites form in the lower zones of soil profiles and represent deep weathering of the bedrock surface. In most outcrops, its color comes from ferric compounds. Deeply weathered profiles are widespread on the continental landmasses between… Read more.
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Detritus (geology)
Detritus is particles of rock derived from pre-existing rock through weathering and erosion. A fragment of detritus is called a clast. Detrital particles can consist of lithic fragments (particles of recognisable rock), or of monomineralic fragments (mineral grains). These particles… Read more.
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Diagenesis (the Petrologic principle)
Diagenesis is the process that describes physical and chemical changes in sediments first caused by water-rock interactions, microbial activity, and compaction after their deposition. Increased pressure and temperature only start to play a role as sediments become… Read more.
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Flame Test
A flame test is relatively quick test for the presence of some elements in a sample. The technique is archaic and of questionable reliability, but once was a component of qualitative inorganic analysis.… Read more.
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Langgan 琅玕 is the ancient Chinese name of a gemstone which remains an enigma in the history of mineralogy; it has been identified, variously, as blue-green malachite, blue coral, white coral, whitish chalcedony, red spinel, and red jade
It is also the name of a mythological langgan tree of immortality found in the western paradise of Kunlun Mountain, and the name of the classic waidan alchemical elixir of immortality langgan huadan 琅玕華丹 “Elixir Efflorescence of Langgan”. Waidan,… Read more.
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In Chinese alchemy, elixir poisoning refers to the toxic effects from elixirs of immortality that contained metals and minerals such as mercury and arsenic
In Chinese alchemy, elixir poisoning refers to the toxic effects from elixirs of immortality that contained metals and minerals such as mercury and arsenic. The official Twenty-Four Histories record numerous Chinese emperors, nobles, and officials who died from taking elixirs to prolong their lifespans.… Read more.
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Cold-Food Powder or Five Minerals Powder, poisonous psychoactive drug popular during the Six Dynasties (220–589) and Tang dynasty (618–907)
Cold-Food Powder (Chinese: 寒食散; pinyin: hánshísǎn; Wade–Giles: han-shih-san) or Five Minerals Powder (Chinese: 五石散; pinyin: wǔshísǎn; Wade–Giles: wu-shih-san) was a poisonous psychoactive drug popular during the Six Dynasties (220–589) and Tang dynasty (618–907) periods of China. Terminology Both Chinese names hanshisan and wushisan have the suffix -san (散, lit. “fall apart; scattered”), which means “medicine in powdered form” in Traditional Chinese… Read more.
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Manes or Di Manes
In ancient Roman religion, the Manes or Di Manes are chthonic deities sometimes thought to represent souls of deceased loved ones. They were associated with the Lares, Lemures, Genii, and Di Penates as deities (di) that pertained to domestic, local, and… Read more.
