( Fr- tectite; Ger- Tektit; Nor- tektitt; Rus- )
A. Tektite. Moldavite (length - 4.1 cm) from Basednice, Czech Republic. Erich Haiderer Minerals. (© photo by Jeffrey A. Scovil)
B. Tektite. Moldavite in sterling silver wire wrap pendant (height - ca. 3 cm). (© photo courtesy www.wehug.com)
C. Tektite. Moldavite carving - Woman's
head (2.5 x 2.2 cm; weight - 7.0 grams) from Besednice, Czech Republic.
(© photo by Martin Bocian, courtesy www.spadiash.com)
DESCRIPTION: Tektites are glass globules
that are typically less than 5 cm (2 inches), but exceptionally up to
nearly 15 cm (6 inches), in greatest dimension. Shapes
are commonly so-to-speak aerodynamic in that they appear to represent
drops that were moving through the air as they hardened -- see several
designations that have been reported under the REMARKS subheading.
Colors - colorless, green, yellowish green, brown, gray and black
Light transmission - transparent to subtranslucent
Luster - vitreous on fracture surfaces
Breakage - conchoidal fracture
Miscellany - Outer surfaces of tektites range from fairly smooth to rough, and are commonly grooved, and the surfaces of many tektites can be seen to have undergone natural etching, apparently having been attacked by humic acids in the soils. Some tektites include bubbles and/or crystallites, commonly arranged in swirls.
OTHER NAMES: Tektite is a group name for natural glasses whose origin is briefly discussed under the REMARKS subheading. Some tektites utilized as gemrocks have been referred to the geographically based designations given in the scientific literature -- see those listed in the fifth paragraph under REMARKS. Others have been given names like to following:
USES: In the distant past, tektites
were used as
talismans (at least in Australia and China) and apparently for making tools (e.g., moldavites in
and perhaps other tektites
elsewhere). More recently tektites have been marketed uncut (but
mounted), as both
cabochons and faceted stones for jewelry, and rarely for small
carvings (see Fig. C).
general characteristics of tektites and most of the pieces I have seen
them, my feeling is that their primary appeal is usually based on their
anticipated value as conversation pieces. I agree with Frederick
(1966), who said, "Once cut, they have the charm and brilliance of a
of beer bottle; best to keep them as they are found." It
certainly seems me that the best (most fruitful) approach would be to
market them as they are
found -- i.e., uncut --
either mounted or not; this way the individual characteristics of
virtually any of them would provide fine conversation pieces.
((An aside: A
non-human, non decorative use is reported on the Australian Museum web
site (www.amonline.net.au/ ): "Emus have been known to swallow
Australites for gizzard stones which help grind up their food."))
OCCURRENCES: See paragraph five under the REMARKS subheading.
NOTEWORTHY LOCALITIES: Most moldavite from the Czech Republic marketed within the last few years has been recovered illegally, usually during night-time hours, and first become available -- as both rough tektites and carvings -- at local mineral fairs (M. Bocian, personal communication, 2003). See also REMARKS.
REMARKS: The word tektite was first applied to these glassy masses by Suess (1900, p.194), who based the name on the Greek τήχτος (sic -- should be τήκτος - melted [German schmelzen]), which is the past participle of τήκειν (to dissolve or melt with fire -- e.g. a metal, wax or other hard mass [German, geschmolzen]). Names widely applied to most tektites are based on the geographic regions where they occur, several examples of which are noted in the fifth paragraph under this subheading. Individual specimens are frequently described on the basis of their shapes, by using adjectives that relate to rather widely known objects -- e.g., ball-, bean-, bowl-, button-, cudgel-, disk-, dumbbell-, gherkin-, peanut-like, hourglass-, lens-, mushroom-, pear-, rod-, and teardrop- shaped. In addition, also because of their shapes, they have been called, in the vernacular, by ridiculous names such as "emu eyes" by Australian aborigines and "Blackfellows' buttons" by early white settlers of Australia.
In prehistoric times, tektites were apparently considered to be religious or magical objects by some people and omens of evil by others. Baird (1993) notes that tektites were “described in China as early as the tenth century by Liu Sun who wrote "In Leichow, after sudden rainstomms (sic), people collect black stones in the field which they call 'leigong-mo', meaning inkstone of the thunder-god."” Also, some Australian aborigines are said to have venerated tektites as "sky charms." In addition, the investigators that have identified yellow-green scarab decoration and necklace on the carved wooden mannequin head of ancient King Tutankhamun (ca.1333-1323 B.C.) of Egypt as fashioned from natural desert glass apparently formed as the result of a meteorite impact.According to Turnovec (1987) moldavites were used rather widely as pendants and as the heads of walking canes in central Europe and were "exhibited and sold, cut and set in gold, already at the Jubilee Exhibition held in Prague in1891." He also notes that the first noteworthy account of these masses was by J. Mayer in a publication dated 1787. Later, in the mid 1800s,Charles Darwin (see 1891 reprint), apparently on the basis of his examination of one of the button-shaped australites, incorrectly ascribed a volcanic origin; he concluded that they represent obsidian bomb(let)s. In addition, well into the 20th century, tektites in general were rather frequently referred to as glass meteorites or as "moon splash" by romanticists and even by some scientists.
Today, the general consensus of the scientific community is that most, if not all, tektites represent splattered melted products of terrigenous soils and rocks formed as a result of shock-melting when large hypervelocity meteors, asteroids and/or comets collided with the Earth. Questions, however, remain -- e.g., why have tektites been associated with only some of the known large meteors that impacted the earth (?).This ruling hypothesis is based largely on the compositions and distributions of tektites: Their compositions tend to mimic compositions of earth materials probably impacted and their distributions comprise belts -- e.g., the previously mentioned moldavites of central Europe; the tektites called australites, billitonites, indochinites, indomalaysianites, java(n)ites, malaysianites, and philippinites (=rizalites) that occur in a northwest-southest trending belt that extends from Indochina, through the Philippines, and across Australia; the bediasites named for their occurrence in the vicinity of Bedias, Grimes County, Texas; the georgiaites, georgiantites, and empirites from near Empire, Dodge County, Georgia, U.S.A.; and the ivorites of the Ivory Coast of Africa. Libyan Desert Glass, which has been fashioned into gemstones and been included on some lists of tektites is also worthy of note here: On the basis of its chemical composition, the shape of most of its fragments and its occurrence, it seems more likely to represent portions of an impactite.
For what it may be worth, it is my opinion that several questions remain, and it may well be that there are tektites and tektites -- i.e. different tektites may have different origins.
Recently reported associations relating tektites, and consequently their ownaetc.]" are, in my opinion, yet another example of markeplace bunco. Anyone interested in such flimflam can find it on the internet.
SIMULANTS: A recent publication by Funda (2015)
includes pertinent information, especially relating to moldavites.
Glass portions of impactites -- [for pieces
in, for example, small carvings, it might be impossible to
distinguish as other than part of a tektite].
***Glassy slag - [in natural form lacks shapes of tektites; after fashioning into a gemstone or the like, tests utilizing relatively sophisticated equipment often required].
***Man-made glass - [If made to imitate tektites chemically, differentiation could be next to impossible; in general, however, man-made glass is rather easily melted whereas most tektites (and obsidian) are not.] Along this line, most of the glass usually referred to as "Beach Glass" is Man-made glass. In any case, the North American Sea Glass Association has recently held a annual contest that makes awards for to collectors for some of the diversely colored pieces of glass that have been given their current characteristics -- e.g., smooth edges -- as a result of erosion they have undergone within oceans, the Great Lakes, etc. .
Obsidian - [See preceding criteria and comments
REFERENCES: Baker, 1963; Barnes, 1961; Barnes and Barnes, 1973; Bouska, 1980; Bouska, Frydrych and Turnovec, 1985; Bouska and Konta, 1986; Futrell, 1999; Suess,1900.
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