Raman spectra of a range of differently aged samples of natural resins (recent resins, copals, fossils resins from Tertiary to Early Cretaceous age) were taken for a comparative study of the age‐induced maturation processes of the resins. It can be shown that a decrease in band intensity at around 1640 cm−1 due to loss of ν(CC) stretching vibrations, together with other spectral details, is correlated with the increase in age of the resins. Copyright © 2001 John Wiley & Sons, Ltd.

The fossil resin siegburgite is known from two localities in Europe: Siegburg, near Bonn, and the 'Goitsche,' near Bitterfeld, both in Germany. Raman spectroscopic data on the material proved the polystyrene character of siegburgite and therefore supported the chemical investigations conducted previously. Cinnamic acid, which was identified as a major constituent in recent resins of Liquidambar ssp. (Hamamelidaceae), was included as a standard pointing towards the origin of siegburgite in the Hamamelidaceae. The rapid and non-destructive method used permits a quick distinction of fossil resins, especially when different resin types occur together in the same deposit, as in Bitterfeld.

No abstract

The Conquista chondrite consists of major olivine, low‐Ca pyroxene (both ortho‐ and twinned clino‐), troilite and metallic nickel‐iron; minor glassy to microcrystalline material and pigeonite; and accessory chromite, high‐Ca clinopyroxene and hydrous ferric oxides that formed by terrestrial weathering of metallic nickel‐iron. Results of microscopic, electron microprobe, and bulk chemical studies, particularly the compositions of olivine (Fa17.2) and low‐Ca pyroxene (Fs15.4); the contents of metallic nickel‐iron (18.5%) and total iron (25.83%); and the ratios of Fe°/Fetotal (0.64), Fe°/Ni° (9.59) and Fetotal/SiO2 (0.69) indicate H‐group classification. The pronounced, well‐developed chondritic texture; the slight compositional variations in constituent phases; the high Ca contents of pyroxene and the presence of pigeonite, glassy to microcrystalline interstitial material rich in alkalis and SiO2, and of twinned low‐Ca clinopyroxene suggest that Conquista is of petrologic type 4.

No abstract