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to hornblendites and holds large and small remnants of the sedimentary
and voleanic strata that once overlay the plutonic rocks. The various
rock types in places gradually pass into one another, whereas in other places
different varieties cut one another. The included bodies of sediments
and voleanies vary greatly in size, ranging from areas of many square miles
down to such as are measurable in feet. These older rocks also vary in
character from such as seem but little disturbed and comparatively unal-
tered, to others which show all gradations from clearly recognizable sedi-
ments or voleanics, to vague areas of rock so altered both physically and
chemically as to appear as local phases of the plutonic rocks.

In the vicinity of the mineral claims on West Redonda, the plutonic
rocks range in character from hornblende granite to diorite of medium
grain and seemingly grade into fine-grained, darker types. With these
rocks are associated many isolated masses of limestone, in places altered
to garnetite, and of fine-grained, dark rocks possibly representing recry-
stallized voleanic rocks. These bodies of sediments and volcanics seem
to occur partly in narrow bands, some of which are many yards in length,
and partly as detached blocks and masses characterizing narrow, band-
like areas. In addition, dyke rocks of various types are present.
A short distance east of the mineral claims, a wide band of white crystalline
limestone is exposed at the shore and is reported to extend far up the
mountain slope. The complex of rocks visible in the vicinity of the
mining claims-seems to mark a zone of disrupted and partly assimilated
sediments and volcanics once part of a large body of bedded strata which
included the wide limestone band, but from which they are now separated
by the intrusive granitic rocks.

DESCRIPTION OF THE ORE OCCURRENCES

Outcrops of magnetite were seen at three localities whose relative
positions are indicated on Figure 14. They lie on a nearly straight line
following a southeasterly direction. The most northerly occurrence
(locality “A” Figure 14), is on the Elsie mineral claim and is situated at
an elevation of 400 feet and is distant 200 yards from the seashore. At
this place a magnetite body between 50 and 55 feet long and haying a
maximum breadth of 20 feet has been stripped and partly quarried. The
outcrop has the outline of an elongated oval whose major axis strikes
southeastward. The mass lies on a steep hill-side and shows in a broken
face 20 to 30 feet high. The northeast edge, on the downhill side, is
concealed beneath the refuse-covered floor of the quarry, but presumably
no considerable part of the mass would have been deliberately buried
beneath waste rock and, therefore, it is assumed that practically the whole
ore mass is still exposed.

At the northwest end of the outcrop the magnetite is sharply separated
by a nearly vertical plane from what is presumed to be a porphyritic phase
of the widespread dioritic rocks, and this same porphyritic rock extends
for a few feet southeastward along the southwest boundary to where it
ends against brownish and pinkish garnetite. The contact between the
porphyry and garnetite runs up hill away from the ore-body. The garnetite
forms the southwest boundary for a few feet, but beyond this the rock
bounding the ore is a dense, compact, greenish rock holding seams of
magnetite and small splotches of garnet. Dense, greenish rocks border