240 
as Syenite. These quarries were once the most actively worked 
in the Island. The Mount Mado granulites contain a red 
Orthoclase which gives the pervading colour to the stone, also 
a white felspar, Albite, but this occurs only at certain places in 
this granulite. The quartz is vitreous and in large proportion, 
interspersed are some spots and spangles of black mica, which _ 
are occasionally drawn together in aggregates. On the exposed 
rock and the floor of the quarry, the old rock is decayed and 
weathered into a depth of loose gravelly material that can be 
freely dug with a spade, and therein may be easily collected, 
single or twinned crystals of Orthoclase—the latter are mostly 
of the Carlsbad type. 
3. GRaNULITE From Matvern Hirt— 
The position of this rock is toward the summit of the 
Worcestershire Beacon, lying to the South side of the trans- 
verse fault between the Beacon and the North Hill. The 
position of the granulite being given, the structure of it may 
be seen figured and described by Mr F. Rutley, F.G.S., in his 
paper on the Malvern Hills.* It is described as a very fine 
grained pale pinkish grey crystalline rock, consisting of pinkish 
felspar, quartz, and minute deep red grains, seemingly of 
garnets. The grains composing the rock are all of them 
irregular in form, and appear to be bound together by a crypto- 
crystalline cement. The felspar appears to be Orthoclase— 
while the quartz contains numerous fluid lacune, some of them 
with bubbles which exhibit spontaneous movement when exam- 
ined under a power of about 800 linear. 
The rock is a granulite, and in common with rocks of this 
class is remarkably tough under the hammer. Portion of a thin 
section as it appears between crossed nicols, and magnified 55 
linear, is shown in Pl. XIX. fig. 8. 
This granulite seems to form a marginal banding, South of 
and contiguous to the granitic mass of the Worcestershire 
Beacon, and may possibly be a condition of the granite with 
changed structure induced by rate of cooling or other influences. 
* V. Q.J.G. Soc., vol xlxxx. page 481. 
