DIMENSION STONES
Introduction.
Tanzania has a wide potential of rocks that can be extracted as
dimension and cut include granite, gneisses, marbles, travertine and
anyolite
Granites.
Potential granite deposits occur in the Tanzanian Craton and in the
Ubendian Super group in southwestern Tanzania. They occur in the regions
of Dodoma, Mbeya, Morogoro, Mwanza, Singida and Tabora (Kanza, 1999). The
granites occur in a variety of colours including pink, grey and black.
They are generally fine to coarse grained.
- Outcrop of Nakapanya Granite, Masasi(Photo by P.Semkiwa)
- Scanned Image of polished black granite.
Marbles.
Potential marble occurrences for prospecting, including white,
blue, whitish grey, grey and pink-cream with green sports, occur in the
eastern part of the country, that is in Bagamoyo, Handeni, Matombo-Uluguru
Mountains, Kiborian-Uluguru Mountains, Mahenge plateau, Kihumbi-Igawa and
Tanga areas (Mbasha, 1995). The rocks are also located in the northwestern
part of the country in the Arusha and Kilimanjaro (Hai and Rombo
Districts) regions.
Travertine.
Travertine containing calcareous onyx occurs at Songwe Valley in
Quaternary volcanic deposits of Rungwe. Resources are known to be in the
order of 72million tonnes. The rocks can be cut into sizeable blocks. The
deposit has been mined since 1991 by Consolidated Mines (T) and Natural
stone Products process the material at Mbeya town
Appinite.
Appinite is a dark coloured hornblende-rich plutonic rock that is
located west of Iringa town and in the Uluguru Mountains.
Anyolite.
Anyolite is another rock type suitable for exploitation for dimension
and cut or art stones. The rock consists essentially of amphibole
chromiferous zoisite and ruby corundum and is exposed in
Merkenstein-Longido, north of Arusha and Dudumera near Babati.
- Pink granite outcrop at Singida(Photo by P.Semkiwa)
- Scanned Image of polished pink granite.
Quartzite.
Quartzite is found in the Chipogolo and Mafurungu/Simbanguru areas in
the Dodoma Region, Kilosa in the Morogoro Region and Kinyangiri are in the
Singida Region.
Basalt and Phonolite.
Basalt, phonolite and other volcanic rocks are widespread in the
Arusha and Kilimanjaro regions northeastern Tanzania and in the Rungwe
volcanic in the southwestern part of the country.
Slate and Flagstone.
Slate and flagstone are developed in the Musoma, Sumbawanga and Kigoma
Districts and Chimala area near Mbeya town.
Outcrop of grey granite. Common in central regions of Tanzania.(Photo
by P.Semkiwa)