its small amount of succinic acid. Only a few insect and 
leaf inclusions have been found in burmite, and the plant 
source has not been indicated (‘T'schirch and Stock, 1986). 
Williamson (1982) reported that in addition to burmite, 
other fossil resins are mined in Asia at Vladivostock, in 
Siam, Cochin-China, Manchuria, Kamchatka and Sak- 
halin. Neither the age nor the plant derivation of the 
ambers has been discussed. 
Brown coals of both Kocene and Miocene age are wide- 
ly distributed throughout Europe, but have been ex- 
ploited particularly in Germany. Because of their com- 
mercial importance, much is known about them. There 
has been considerable study of the wood in the Rhine coals 
(Jurasky, 1981, 1988; Schénfeld, 1958), as well as of fruits 
and seeds (Kirchheimer, 1986, 1987, 1957; Weyland, 
1934 et al.), of leaf cuticles (XKrausel and Weyland, 1951, 
1954) and of pollen (Potonié and Venitz, 1984; Pflug, 
1957; Thomson, 1958 et al.). Resin apparently consti- 
tutes about 3% of most humic brown coals (Henderson, 
1958). Reports of resins from European brown coals have 
been relatively common (Steinbrecher, 19385; Tschirch 
and Stock, 1936 et al.), although these resins have not 
received the attention that Baltic succinite has. Stein- 
brecher contrasts two types of resin from the brown coals: 
‘*Bitumenharze’’ and retinite. The Bitumenharze are 
mixed in the coal with waxes and isolated only by solu- 
tion of the coal matrix. Among the retinites he lists 
eosmite, sheibite, kranztite, muchite, trinkerite, hartite, 
ixolite, and Greenland bernstein. In comparing their 
specific gravities, melting points and carbon, hydrogen, 
oxygen ratios, he concluded that they should be con- 
sidered different types. Because of their relatively poor 
quality and their dispersion as small pieces throughout 
the coal, there has been little investigation of these resins. 
These occurrences are of particular importance in studies 
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