CHAPTER VIII. 
MmEUALOGY -continued. 
Titano-silicates, Niobates, Phosphates, and Tung- 
states. 
Greenovite — Tschefikinite — Columbite— Man^aiiapatite — Triplite — A mangauusian 
phosphate — Wolfram. 
Greenovite. 
Greenovite is a red variety of sphene or calcium titanosilicate 
(CaTiSiOs) found at St. Marcel in Piedmont. It owes its colour to 
a small percentage of manganese. 
In one spot on the small hill at Jothvad in Narukot State, a 
small vein or apophysis from the surrounding granite traverses 
the manganiferous banded rocks forming the main mass of the hill. 
This vein is composed of pink felspar (microcline and oligoclase with a 
little orthoclase), ^^^th a certain amount of interstitial quartz, and a 
large number of prisms and granules of dark-coloured minerals. The 
granules and stumpy prisms consist of a manganese -garnet and blan- 
fordite, respectively. Besides these two minerals, however, there is a 
manganiferous variety of sphene. It occurs in small dark brown 
prisms up to nearly J inch long, which, when detached and placed on 
the stage of the microscope, are seen to be transparent and pleochroic 
in yeUow-green and a pale warm brown, the two colours being of about 
equal strength. The crystals are elongated, simulating a prism, in which 
the apparently prismatic faces are really drawn-out pyramid faces, n 
(111), the crystal being several times as long as broad. At the ends 
they are terminated by faces that are probably c (001), a (100) and m (110) 
these faces being all of small size compared with the n faces. The crystals 
are in fact very similar to that shown in figure 6, page 713 of Dana's 
System of Mineralogy, 6th edition, with the exception that the x face 
is wanting and the n faces are very much elongated in the direction of 
the vertical axis. The mean value of the angle nn' as measured on the 
reflecting goniometer over two edges of a crystal was found to be 43° 30', 
whilst the value given by Dana is 43° 49'; the images were not very 
bright or distinct. In thin sections imder the microscope the mineral 
is found to be biaxial, and to show the very high refractive index and 
