298 Florence J. Relf—Some Wealden Sands. 
(1) Crystals long, length four or five times breadth, with sharply 
pointed pyramids developed at both sides. (Pl. XII, Fig. 1.) 
(2) Crystals short, length about twice the breadth, with pyramids 
at both ends. 
(3) Crystals with only one pyramid developed. These may show 
a basal plane at the other end, or they may appear irregular at that 
part, as though broken off (as they would look if they had grown in 
a cavity). (Pl. XII, Fig. 2.) 
(4) The fourth type is a modification of types (2) and (8), and 
includes short crystals rounded at the ends, making the whole 
fragment oval in shape. 
Of these, type (2) seems to be commonest. Many crystals have 
inclusions; a few show zoning. 
Some idea of the abundance of zircon crystals can be obtained from 
the results of counting in the case of eleven specimens from Heathfield. 
In 1 gm. of sand the zircons varied in number from 55 to 877, the 
average being 288. Though the figures are certainly not accurate 
they serve to show that the mineral is common among the heavy 
constituents. In the heaviest portion of the sand (s.g. above 3°317) 
it is the predominant mineral. The size of the crystals is fairly 
constant, the length varying, in the examples measured, between — 
°04 to °09 mm. 
Tourmaline.—Next to zircon, among the heavy minerals of these 
sands, tourmaline is the most abundant, and the blue and the brown 
varieties are present. The brown tourmalines are generally larger 
than the blue ones, and they have quite irregular outlines. The blue 
ones are as usual more definite in shape, often showing a tendency to 
| prismatic form. Individuals of both varieties are generally broken, 
but seldom rounded. (PI. XII, Fig. 3.) Their size is less variable 
than that of the quartz grains, being from ‘05mm. to‘lmm. As 
a result of the counting previously referred to, the number of 
tourmaline grains per gram of sand was found to vary from 12 to 105, 
the average being 58, far less than the number of zircons. 
Rutile comes next in point of abundance. The crystal shape is 
generally good, and the characteristic geniculate twinning is 
occasionally recognizable. 
Staurolite.—This mineral is rare, but a little was identified in the 
sand from Lindfield, and more in that obtained from west of Bexhill. 
Kyantte also is rare, and was only found in the Bexhill specimens 
and in those from France. (Pl. XII, Fig. 5.) 
Anatase, although not common in these sands, was recognized in ~ 
the Bexhill and Lindfield samples. Some crystals show the striated 
steep pyramid-faces, and others are tabular. (Pl. XII, Fig. 4.) 
Garnets were only recognized in the Lindfield Sands. 
Fluor was identified in one of the Lindfield samples. 
As the materials found in these sands make it probable that the 
rocks from which they were originally derived were of granitic 
character, it was decided to powder some granite and to attempt 
a separation of its heavy minerals by the same method as that used 
for the sands. The granite chosen was from Corndon, Dartmoor, this 
being the nearest granitic area to the Weald. It was crushed in 
