Alkaline Rocks and Carbonatites of the World

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

Macula

stripes

Occurrence number: 
005-00-026
Country: 
Angola
Location: 
Longitude: 13.77, Latitude: -13.68
Carbonatite: 
No

In the Serra da Macula is an occurrence of nepheline-bearing syenite consisting of 76% orthoclase, 2% oligoclase, 0.25% nepheline, 7% biotite, 6% titanaugite, 2% barkevikitic amphibole, 2% olivine, 4% opaque minerals and 1% apatite. A chemical analysis is available (Gonçalves, 1965). Lapido-Loureiro (1969) reports both syenite and nepheline syenite at this locality.

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. LAPIDO-LOUREIRO, F.E. 1969. Structures sub-volcaniques carbonatitiques d'Angola. Relatórios e Comunicações do Instituto de Investigação Científica de Angola, Luanda, 5: 11-20.

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