Alkaline Rocks and Carbonatites of the World

Setup during HiTech AlkCarb: an online database of alkaline rock and carbonatite occurrences

Chicacimo (Macico Tama)

stripes

Occurrence number: 
005-00-027
Country: 
Angola
Location: 
Longitude: 13.58, Latitude: 13.92
Carbonatite: 
No

This occurrence comprises tuffs and feldspathoidal syenites. A nepheline-sodalite syenite comprises 49% orthoclase, a little oligoclase, 29% nepheline, 4% sodalite, 13% aegirine-augite, 1% biotite and accessory opaques, titanite, apatite and calcite. A more leucocratic variant contains 67% orthoclase, 4% oligoclase, 15% nepheline, 6% sodalite, 3% aegirine-augite, a little hornblende and accessories. Analyses of both rock types are given by Gonçalves (1965).

References: 

GONÇALVES, F.G. 1965. Nota sobre algumas rochas alcalinas da região Impulo-Chongorói. Boletim. Serviços de Geologia e Minas Angola. Luanda. 12: 95-107.

Location: 
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith