Natural bismuth vanadate from the Mutala pegmatite area, Mozambique
✍ Scribed by O. Knorring; Th. G. Sahama; Martti Lehtinen; Pentti Rehtijärvi; Jaakko Siivola
- Book ID
- 104745816
- Publisher
- Springer
- Year
- 1973
- Tongue
- English
- Weight
- 820 KB
- Volume
- 41
- Category
- Article
- ISSN
- 0010-7999
No coin nor oath required. For personal study only.
✦ Synopsis
Bismuth vanadate (microprobe test) in varying shades of orange color and in well developed crystals (averaging 0.2 mm in size) occurs in bismutitc in the Mutala granite pegmatite area, district of Zambezia, Mozambique. Two modifications of BiVO~ were identified. An orthorhombic form is identical with pucherite and shows a 0 = 5.33~ A, b 0 = 5.05~ A, c o = 12.021 A. The crystal habit ranges from platy to stout prismatic. The X-ray powder pattern of the monoelinic form matches that of the synthetic monoclinic Bi-orthovanadate with a0=5.205 A, b 0 = 11.71 s A, c o = 5.09 s A, fi = 90 ~ 25'. The crystal habit resembles that of a pyramidal seheelite crystal with the b-axis corresponding to the scheelite c-axis. Multiple twinning is seen on ( 101), in some instances with a composition plane (010).