Комиссия IMA по новым минералам и названиям минералов: нормы и рекомендации по номенклатуре минералов, 1998 Биогенные веществаBiogenic substances
It is not always possible to draw a sharp distinction between biogenic substances, i.e. those produced by biological processes, and minerals, which are normally produced by geological processes. For instance, it is becoming increasingly clear that many of the processes associated with diagenesis are influenced, to some extent, by bacterial action, and the biosphere is commonly regarded as an integral part of the geochemical cycle. Nevertheless, it is necessary to make a formal distinction so as to prevent a host of purely biological materials being incorporated into the world of minerals. Some biogenic substances, such as hydroxylapatite in
teeth, whewellite in urinary calculi or aragonite in the shells of molluscs, also exist as minerals formed by geochemical processes, and therefore are regarded as valid minerals. However, purely biogenic substances that have no geological counterparts, or whose origin owes essentially nothing to geological processes, are not regarded as minerals.
However, substances formed by the action of geological processes on organic material, such as the chemical compounds crystallized from organic matter in shale or from bat guano, can be accepted as minerals.
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