Other small occurrences of Cretaceous amber have 
been reported from: Hardin County, Tennessee; the 
Black Hills of South Dakota; Canon Diablo of Arizona: 
the coals of Kagle Pass and ‘Terlingua Creek in Texas; 
and Baja California. Coals from Coalmont, British Co- 
lumbia, also contained amber which is used commercially 
for varnish. There has not been a general investigation 
as yet of these ambers, and no plant source has been 
indicated. 
By far the most extensive deposits of amber thus far 
discovered occur in more or less isolated basins of Eo- 
Oligocene strata along the shores of the Baltic Sea from 
Kstonia to Denmark. The largest amber mines were 
located in the basin on the Samland Peninsula at Palm- 
nicken. Because this amber has been studied more inten- 
sively than any other, it has provided the classical concept 
of amber for most laymen and even for most scientists. 
In fact, it has led to preconceptions concerning the bo- 
tanical sources of ambers in general. For these reasons, 
the Baltic amber will be discussed separately in a later part 
of this paper and in more detail than the other deposits. 
Copalite or Highgate resin occurs as irregular pieces 
of pale, honey-colored material in the Kocene London 
Clay formation from the southeast coast of England. 
W hitaker(1889)stated that this amber resembles ‘‘copal’’ 
in hardness, color, transparency and relative insolubility 
in alcohol. There is some semantic confusion, as the term 
‘“*copal’’ is used to connote resins from different families 
of plants. Probably reference here is made to African 
copal of commerce which comes from such leguminous 
genera as T'rachylobium and Copaifera. The affinities of 
the London Clay Flora are considered by Reid and 
Chandler (1933) and Chandler (1961) to be predominantly 
tropical, with most of the flora allied to genera inhabit- 
ing present-day tropical or montane rain-forests of Indo- 
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