Mem. Nat. Mus. Vict., 14, 1944. 
FLANGES OF AUSTRALITES (TEKTITES). 
By George Baker , M.Sc., 
Geological Department , Melbourne University. 
Plates I-III. 
Introduction 
Flanges of australites are equatorial projections between the 
posterior and anterior surfaces (Fig. 1) ; they are broad and thick 
compared to the rims of some specimens, and they usually curve 
towards the posterior surface. Incipient flanges are called rims. 
The literature of australites, which has been listed by Fenner 
(1938) and by Barnes (1940), contains few details of structural 
features of flanges. Dunn (1912 b) figured thin sections showing 
flow lines in the glass of which they are composed ; he attributed 
australites to “blebs” on glass bubbles escaping from volcanoes, 
the flanges being part of adjacent walls of the bubbles. Fenner 
(1938) reviewed theories of origin and gave reasons for consider- 
ing that australites are glassy meteorites and that the flanges 
result from flow of molten material during transit through the 
atmosphere ; these theories are generally accepted. 
The following observations are based on study of 137 flange 
fragments, 9 complete detached flanges, 72 fragments of australites 
and several complete examples. Most of the material came from 
the Port Campbell district, Victoria. Many thin sections were 
prepared. 
Australites are grouped according to shape. Most of them are 
shaped like buttons, ovals, dumb-bells, lenses, discs, boats, tear- 
drops, canoes and cores, but there are also aberrant forms such 
as “air bombs” and “crinkly tops” (Fenner, 1934). 
Few flange fragments can be assigned to australites of shapes 
other than buttons, since few are sufficiently large to indicate the 
shape of the australites of which they formed a part. The majority 
are assumed to come from buttons because buttons are by far the 
most abundant type. Oval fragments are rare. 
Some flanges are complete, others are imperfect owing to loss 
of a portion during flight or subsequently. Flanges completely 
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