Chap. XXVIII.] use as colouring material. 
603 
The next recipe is that in use for a black body clay for plaster 
moulds and the potter's wheel : — 
Recipe No. 63. 
rts by measure. 
Black broken pipes ....... 3 
Uncalcined kankar i ....... 2 
Durgapur clay ........ 2 
Giri mati (red ochreous clay) ...... 2 
Manganese-ore ......... 1 
Then take of 
Recipe No. 63 3 
Felspar and biscuit mixed ...... 1 
The materials are all passed through a small washmill and sieve of 120 
holes to the linear inch. This latter recipe is used for producing statuary, 
vases, jeroboaras, and other ornamental ware. When unglazed this 
ware is very similar in colour to psiloraelane, emits a heil-like sound when 
struck, and is extremely hard and tough. Just the merest trace of 
glazing changes the colour to slaty-black, and when adorned with silver 
monogram, or other silver ornamentation, articles of this ware are ex- 
ceedingly handsome. 
Manganese -ore is also used for glazing terra-cotta biscuit-ware, the 
colour produced varying, according to the proportion of ore used, from 
chocolate to pure black. The following recipe is one now in use for im- 
parting a deep brown glaze to such articles as teapots, chilams, and 
hookahs : — 
Parts by weight 
White lead 12^ 
Cornish stone ^ ....... . 3 
Calcined English flint ....... 2i 
Manganese-ore ......... 2\ 
Durgapur clay ......... \^ 
By increasing the proportion of manganese-ore a deep black colour is 
obtained. Articles — presented by Mr. A. Whyte of Messrs. Burn k Co., 
to whom I am indebted for the foregoing information — illustrating the 
foregoing recipes Avill be found in the Geological Museum. 
The ore used is all obtained from the neighbourhood of Sihora and 
Gosalpur in the Jabalpur district. The pyrolusite and psiloraelane of 
this district are often mixed with quartz and clay ; but these foreign 
materials do not spoil the ore for pottery purposes, for which it need 
not be particularly pure. 
1 Real]-- disintegrated la'erite. 
2 Residue from Cornish kaolin. 
