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CORE NO. 4
Cominco VS-1
Core (hand sample) description:

Feet below surface	Description
1806 - 1844	Phenocrysts of feldspar in dark matrix. Probably diorite.
1844 - 1852	Similar to above, but some replacement with hematite / iron minerals.
1852 - 1900	Diorite, same as top of core. Thin section taken at 1879 feet.
1900 - 1938	Dark grey rock with very small visible crystals. Probably gabbro.
1938 - 1946	Holocrystalline granitic rock with up to 30% dark minerals.
1946 - 1970	Heavily altered felsic rock with hematite coating.
1970 - 1972	Missing.
1972 - 1975	Looks like granular hematite. Possible paleosol?
1975 - 1985	Heavily altered felsic rock with hematite coating.
1985 - 1999	Granite.
1999 - 2010	Fine-grained felsic rock.
2010 - 2014	Alteration zone. Banded rock with layers of quartz between pale green and maroon minerals.
2014 - 2022	Gabbro with dark minerals altering to green. 20% visible white feldspar.
2022 - 2024	Granite. Contact to above rock gradational.
2024 - 2033	Gabbro with some pink feldspar, gradational to above granite
2033 - 2034	Dark grey gabbro, foliated, with fractures along foliation.
2034 - 2045	Dark grey gabbro.
2045 - 2114	Holocrystalline granite. Crystal size increses with depth.
2114 - 2132	Dark grey gabbro.
2132 - 2134	Intrusion of heavily fractured holocrystalline rock. Chilled contact to host.
2134 - 2143	Dark grey gabbro.
2143 - 2145	Granitic rock with up to 30% dark minerals.
2145 - 2149	Dark grey gabbro with phenocrysts of white feldspar.
2149 - 2156	Holocrystalline granitic rock with up to 30% dark minerals.
2156 - 2192	Dark grey gabbro.
2192 - 2193	Pale grey holocrystalline granitic rock. Large (to 1 cm) crystals of white feldspar and quartz.
2193 - 2198	Dark grey aphanitic gabbro.
2198 - 2204	As at 2192 - 2193.
2204 - 2291	Dark grey gabbro.
2291 - 2292	Holocrystalline granitic rock containing pink feldspar. Gradational contact above and below.
2292 - 2303	Dark grey aphanitic gabbro.
2303 - 2322	Dark grey gabbro, with lighter mineral content increasing with depth.
2322 - 2331	Dark grey gabbro.
2331 - 2333	Granitic intrusion containing pink feldspar.
2333 - 2336	Dark grey aphanitic gabbro.
2336 - 2337	Marbled appearance. Dark and light swirls. Quartz veining and larger phenocrysts of quartz and white feldspar.
2337 - 2352	Equal proportions of quartz and dark minerals. Shape of phenocrysts give rock a �wormy� appearance.
2352 - 2399	Dark grey gabbro with yellow-green minerals up to � cm long.
2399 - 2402 (TD)	Dark grey gabbro variably mixed with pink to white granitic rock. Biotite in both. Thin section taken at 2399 feet.

Thin section description:

1879 feet:

Plagioclase	70 - 75% content of rock. Albite and carlsbad twinning; much heavily altered to sericite. Some crystals show ophitic texture with pyroxene. Optic angle 30�.
Pyroxene	20 - 25% of rock.
Biotite	3% of rock. Primary. Dark red-brown color.
Calcite*	associated with sericite.
Quartz*	possible interstitial.

^*Calcite and quartz together less than 2% of rock.

Name: Biotite gabbro.

2399 feet:
Thin section taken at contact between gabbro and granitic intrusion.^*

Gabbro:

Plagioclase	50 - 60% of rock. Albite and carlsbad twinned, variably altered to sericite. Some crystals show ophitic texture with pyroxene/chlorite. Optic angle 30�.
Pyroxene	35 - 40% of rock. Mostly altered to chlorite.
Biotite	To 5% of rock. Primary. Dark red-brown color.
Opaques	Finely disseminated about central nuclei; also along parting plane of pyroxenes.

Name: Biotite gabbro

Intrusion:^*

Quartz	45% of rock.
K-spar	45% total content. Orthoclase and microcline in about equal proportions. Some minor perthite. Variably altered, less so for microcline.
Biotite	5% of rock. Primary. Dark red-brown color.

Name: Biotite alkali-feldspar granite.
^*Note: thin section clearly shows a vein of this granite cutting the gabbro.

CORE NO. 6
Cominco DS-1
Core (hand sample) description:

Feet below surface	Description
1808 - 2078	Dark grey aphanitic rock. Strongly attracted to magnet. Probably gabbro. Thin section taken at 1815 feet.
2078 - 2037	Very aphanitic black rock. Probably diabase. Thin section taken at 2042 feet.
2037 - 2043	Dark grey aphanitic gabbro.
2043 - 2045	Holocrystalline granitic intrusion containing pink feldspar.
2045 - 2123	Dark grey aphanitic gabbro.
2123 - 2126	Granite intrusion.
2126 - 2132	Dark grey aphanitic gabbro.
2132 - 2136	Diabase intrusion.
2136 - 2167	Dark grey aphanitic gabbro.
2167 - 2168	Pegmatite, with phenocrysts of pink feldspar, probably orthoclase, up to 2 inches long.
2168 - 2214	Dark grey aphanitic gabbro.
2214 - 2221	Holocrystalline granitic intrusion containing pink feldspar and xenoliths of host rock (gabbro).
2221 - 2348 (TD)	Dark grey aphanitic gabbro.

Thin section description:

1815 feet:

Plagioclase	60 - 65% of rock. Albite and carlsbad twinned. Optic angle 34�.
Pyroxene	30 - 35% of rock, both ortho- and clinopyroxene. Some twinning. Variable replacement by chlorite.
Biotite	1 - 2% of rock. Primary.
Opaques	less than 1%. In irregular grains and along parting planes of pyroxenes. Probably magnetite (core magnetic).
Apatite	less than 1%.

Name: Biotite gabbro.

2042 feet:

Irregularly oriented plagioclase laths to .125 mm, with carlsbad twinning, and minor amphibole and finely disseminated opaque grains in chlorite groundmass. Some larger plagioclase laths appear zoned.

Name: Diabase.