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Black slate, similar to the Pleasant Valley formation :
Crenulated, red and grey slate, similar to the Pleasant Valley formation

Vein quartz, impregnated with pyrite

Grey and black chert ; a
Coarse-grained, crystalline limestone, similar to the Barkerville formation _
Schistose basic vesicular lava, similar to part of the Pleasant Valley formation

Granular pyrite ; : pean ;
Pebbles and rounded fragments of medium-grained, acidic intrusive rock (probably
monzonite) considerably replaced by carbonates

The smaller rock fragments are well rounded; the larger ones are
angular. The lower part of the formation lacks assortment, and the matrix
is chloritic and micaceous—not gritty as in a transported gravel. These
characteristics are those of a decomposed residual mantle which suffered
little from transportation. Many of the pebbles and fragments are from
rock formations which had been previously involved in regional deform-
ation, and intruded by igneous rocks. ‘The fragments of vein quartz and
granular pyrite may or may not be from the veins in the Cariboo series.
Some of the basal part of the conglomerate was crushed and panned and
this operation revealed the presence of placer gold. This points to a period
of gold mineralization with subsequent weathering previous to the form-
ation of the base of the Slide Mountain series.

Greenberry Formation

Distribution. Intermittent exposures of this formation occur imme-
diately northeast of the Guyet conglomerate, and indeed grade into the
upper quartzite facies of it. The main rock of this formation is lime-
stone, which outcrops prominently on the southern slope of Two Sisters
mountain just beyond the northern limit of the map-area; on the Bear
Lake road northeast of the Guyet conglomerate; on the southwestern
slope of mount Murray; on the southwestern slope and on the south-
easterly extension of mount Greenberry; and in an isolated locality about
2 miles due east of mount Greenberry. The limestone was not located
between the Guyet and Antler formations on mount Howley, or indeed
in any locality southeast of Antler creek.

Lithology. The formation is entirely a medium-grained, grey lime-
stone, seamed with a good deal of dark-coloured chert. The stratification
is only very indistinctly marked. In its two most prominent occurrences
on Two Sisters mountain and mount Greenberry it is highly charged with
crinoid stems, some of which are preserved as chert replacements. It is safe
to say that here nearly half the volume of the rock consists of the crinoids.
The section of the formation exposed along the Bear Lake road consists
of a somewhat thinly-bedded, argillaceous phase of the limestone, in
which crinoids were not discovered, but which contains a few large tubular
structures suggestive of Orthoceras.

Age and Correlation. Careful examination of the Two Sisters Moun-
tain and Mount Greenberry localities resulted in the recovery of a frag-
mentary suite of fossils, which were submitted to E. M. Kindle, of the
Geological Survey, for determination. Of this collection and of the age
of the formation, Mr. Kindle says, in part, as follows: “Specimens of
limestone consisting chiefly of large crinoid column sections comprise the