Eccentrique
Excentriques (French excentrique "eccentric, spun") are a rare sinter formation and belong to the Speleothemes .
Appearance
Excentriques can grow in the cave from all sides . They are very irregular and often hook-shaped, twisted, thread-shaped or worm-shaped.
The peculiarity of eccentriques is that they can grow against gravity .
Emergence
Early geologists already recognized that capillary force is decisive for growth against gravity : According to this, these rare sintered forms consist almost without exception of single crystals , in which the solution supply required for growth can take place both through a central capillary and through a film of moisture on the surface generally does not lead to the formation of crystal faces . For the growth of eccentrics, however, only crystal forces and not gravity are decisive.
literature
- C. Andrieux: Morphogenesis des helictites monocristallines. In: Bulletin de la Société Français de Minéralogie et Cristallographie , No. 88 (1965), pp. 163-171.
- F. Göbel, F. Reinboth: Excentriques, a little known form of calcites. In: Der Aufschluss 23 (4), 1972, 113-124.
- CA Hill, P. Forti: Cave Minerals of the World. 2nd edition, National Speleological Society, Huntsville 1997.