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and September, but shipments in June and July would necessitate bridging —
two large streams, namely, Spanish and Deception creeks. A heavily
laden pack train could make a round trip every three days. The freight
charges from the end of the trail, 20 miles by boat and about 35 by wagon
to the railway grade, would cost from $20 to $25 per ton.

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CHAPTER VII.
CHROMITE, MOLYBDENITE, MANGANESE, AND NICKEL.
CHROMITE.

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Chromite ores lie on Chrome creek (Figure 14) one-quarter to half a
mile above its entrance into Scottie creek, 4 miles by road from the point
where Scottie creek enters Bonaparte river, and a farther 19 miles by
wagon road with an easy grade to Ashcroft on the Canadian Pacific rail-
way (Figure 2, locality 35). The deposit was discovered by Mike Ahearn
in 1901, but was not developed until the first half of 1918 when the price
of chrome and an anticipated shortage stimulated the search for new
ore-bodies. Chrome creek flows between steep banks and has a broad,
flat bottom of easy gradient, but the lower part of Scottie creek lies in a
rather rugged gorge. The hills back of the creek courses are flat-topped
and mostly drift-covered.

The ore mineral at Chrome creek occurs in serpentine rocks and
consists of chromite, or more properly chrompicotite. It is associated

- with some magnetite and carbonates, probably of magnesium and calcium,
and, occasionally with opaline silica, white magnesium sulphates, and
chrome-bearing chlorites and garnets, but the garnets are not commercially
important. Chromite is composed principally of the oxides of chromium and

ferrous iron (FeOCr.O3), with varying amounts of magnesium, aluminum,

- and ferric iron chemically combined. The mineral rarely contains 60 per
cent and sometimes contains only 10 per cent of chromium oxide. In this
connexion it is important to bear in mind that no system of mechanical -
concentration of chromite ore can raise the percentage of chromic oxide
above that contained in chemical combination in the mineral. A sample
of chromite from this locality, Scottie creek, was forwarded to the Geolo-
gical Survey in 1901 and examined and analysed by R. A. A. Johnston!
with the following results: chromium sesquioxide, 55-90 per cent; alumina,
13-83 per cent; ferrous oxide, 14-64 per cent; magnesia, 15-01 per cent;
silica, 0-60 per cent; total 99-98 per cent. Colour, velvet black, opaque ;
in very thin sections, however, translucent, and brownish-red by trans-
mitted light: streak, grey to black-brown, fracture uneven, specific gravity
4-2. Its hardness is about 5-5, it is non-magnetic and it crystallizes in
the isometric system, usually in octahedra. .

Magnetite which occurs with chromite here and elsewhere has approxi-
mately the same colour, lustre, and shape of crystals. It can be distin-
guished from chromite by its streak, which is black, whereas chromite
whem scratched yields a brown powder. Magnetite is in all cases strongly
magnetic, but chromite is rarely magnetic.

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1Geol. Surv., Can.,, Ann. Rept., vol. XIII, 1900,pp.{11-12R. The location is incorrectly stated in this report
because of a mistake by the person who forwarded the sample to Ottawa.