Crystal Cave

Figure 2. Co-variations of 6 Cct and 8 Oc, (given relative to the PDB standard) for some fossil speleothems (73951 - Igloo Cave, Nahanni Region, NWT, Canada 72040 - El Sotano de Soyate, SLP, Mexico 71003 — El Sotano de la Tinaja, SLP, Mexico 73039 — Crystal Cave, Bermuda 71042 - El Sotano del Arroyo, SLP, Mexico 74019 - Coldwater Cave, lA, USA) illustrating isotopic relationships that characterize deposition under equilibrium and non-equilibrium situations (from Harmon, 1975). Meaningful paleoclimate information can only be retrieved from speleothem calcite deposited under conditions of isotopic equilibrium.

Mazzarotta, B., Di Cave, S. and Bonifazi, G., 1996. Influence of time on crystal attrition in a stirred vessel. American Institution of Chemical Engineers Journal, 42, 3554-3558. 

Fig. 1.4 SEM images of caved cuboctahedral hexagonal copper sulfide (CuS covellite) crystals, synthesized by a solvothermal process in ethylene glycol, at 140 °C. (Reprinted in gray scale with permission from [52], Copyright 2009, American Chemical Society)...

Nemati, F., Cave, G. N, Couvreur, P. Lyophilization of substances with low water permeability by a modification of crystallized structures during freezing. Assc. Pharm. Galenique Ind., Chatenay Malabry, 3, p. 487-493, 1992... 

Cave, Krotinger and McCaleb [60] worked out a general method for preparing explosives in the form of fine crystals. It consists of introducing a hot solution into a cold diluting liquid. 

The combined volume of all the billions of open rooms" in the hexagonal ice crystals of a piece of ice is equal to the volume of the part of the ice that extends above water when ice floats. When the ice melts, the open spaces are exaedy filled in by the amount of ice that extends above the water level. This is why the water level doesn t rise when ice in a glass of ice water melts—the melting ice caves in and exactly fills the open spaces. 

Crystallization. Very often it is necessary to obtain explosives (TNT among them) in readily precipitated form. Cave, Krotinger and McCaleb [61] developed a general method of crystallization which consists essentially in introducing the hot solution of a substance into cold diluting liquid or solid carbon dioxide. 

You are probably familiar with the ionic crystals in caves. Stalagmites and stalactites are crystal columns that form when water, containing dissolved lime, drips very slowly from the ceiling of a cave onto the floor below. How do these ionic crystals grow ... 

Topotactic forces affect the ordinary reaction in some other ways. There is the case of a small molecule partidpating in crystalline-state photodimerization (see Sect, m.a.), e.g. small molecules such as water or n-hexane in the atmosphere are involved in the reaction29,30. These small molecules, sometimes even the moisture in the air, not only greatly affect the rate and conversion of the reaction but are also included in the crystal of the photoproduct as a crystal molecule at the end of the reaction. In such dimer crystals, a small molecule may be useful for filling up the cave in the crystal, thus stabilizing the... 

Quartz occurs in dolomite crusts in Carlsbad Cavern, Lechuguilla Cave, and probably other nearby caves, and within unusual iron oxide-rich stalactites (the Rusticles ) in Lechuguilla Cave. Most of the crystals of quartz were euhedral and 10-200 pm in diameter however some exceeded 200 pm in diameter (Fig. 3). In the Rusticles of Lechuguilla Cave, quartz crystals, along with dolomite and calcite, formed cement in the central canal of these stalactites. Within the quartz were filaments of iron-... 

Figure 2. (A) SEM image of amorphous silica dissolved from a late Holocene stalagmite (Hidden Cave). Note the fibrous texture of the amorphous silica. These are molds of aragonite crystals. (B) SEM image of opal botyroids and filaments on an opalline coating on metatyuyamunite crystals (Spider Cave, from Poly Mid Mosoh 1995).

Figure 5. SEM images of Mg-silioate fibers associated widi dolomite said opal (Spider Cave). (A) Mg-silicate fibers appear to grow from pits on the dolomite crystal. (B) Mg-silicate fibers extend from botryoidal opal.

Borsato, A., Frisia, S., Jones, B. Van der Borg, K. (2000) Calcite moonmilk crystal morphology and environment of formation in caves in the Italian Alps. Journal of Sedimentary Research 70, 1171-1182. 

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