Scolecite, thomsonite, and calcite constitute the stable alteration minerals competing for Ca at low temperature, followed by their progressive replacement by epidote, wairakite, and prehnite with increased temperature.
Caption:
Scolecite (Rio Grande de Sol, Brazil) is one of the microporous, aluminosilicate minerals known as zeolites, commonly used as commercial absorbents and catalysts--including producing medical oxygen.
Prakash, "Thin layer chromatographic separation of a few food dyes over
scolecite as a new adsorbent," Chromatographia, vol.
Wise, Thermodynamic studies of zeolites: Natrolite, Msolite, and
Scolecite, American Mineralogist., 68, 1134 (1983).
Very recently, literature survey reveals several methods for synthesis of 2,4,5-triaryl imidazoles using ionic liquid [10], iodine [11], ZrCL, [12], NH4OAc [13], Yb[(OTf).sub.3] [14],
scolecite [15], PEG-400 [16], Lproline [17], HOAc [18], Cu[Cl.sub.2][H.sub.2]O [19], silica sulfuric acid [20], S[O.sub.4]/Ce[O.sub.2] [21], and Sb[Cl.sub.3] [22].
They were followed by acicular-fibrous zeolites such as natrolite/ gonnardite, thomsonite, mesolite and
scolecite Analcime is usually a Na-rich mineral phase, but may sometimes contain appreciable K (Utada, 1970).
An internal standard (
scolecite) was used in addition to the standard regularly used.
A number of other zeolites have also been reported from Merelani, including laumontite and mesolite in tufts of acicular white crystals, and stilbite,
scolecite and chabazite-(Ca).
Merchant could not confirm--that the tiny crystals originally were some zeolite (
scolecite?), now replaced by the opaque white chalcedony.
Powellite on
Scolecite Nasik, India 6" wide (Powellite crystal 3" tall) ex-collection Joseph Freilich
Numerous dealers at this show, as at nearly all major shows these days, had superb specimens of (oh, let's see) Veracruz, Mexico amethyst; Moroccan vanadinite and cerussite; Pikes Peak, Colorado microcline (and even topaz); apophyllite, stilbite, calcite,
scolecite, etc.
Yet even these great mesolite specimens are exceeded in size by several of the 100
scolecite specimens taken in January 2008 from a quarry near Junnar village.