stripes
Occurrence number:
130-00-004
Country:
Paraguay
Region:
Concepcion
Location:
Longitude: -57.57, Latitude: -22.28
Carbonatite:
No
This is probably a complex of dykes, but shown as a major intrusion by Milton and Eckel (1959, Plate 1). It is described as 'phonolite' but comprises phenocrysts of aegirine-augite, orthoclase and andesine/labradorite in a groundmass of partly serpentinized olivine, biotite and feldspar, with crystals of nosean, magnetite and apatite, and secondary zeolite and carbonate.
References:
MILTON, C. and ECKEL, E.B. 1959. Igneous and metamorphic rocks. In Geology and mineral resources of Paraguay - a reconnaissance. Professional Paper, United States Geological Survey, 327: 12-50
Location: