Project
Kas started exploration work at Achmmach in 2007, with the objective of upgrading the small two
million tonnes (Mt) JORC-compliant resource by way of additional diamond drilling.
KSA geologists have noted a general relationship between tin grades and the mode of
occurrence of cassiterite, as outlined in Table 1.
Table 1: Cassiterite occurrence at Achmmach
Grade range Modes of occurrence of cassiterite
Up to about 0.5% Sn Quartz-cassiterite +/- sulphide stringers and veinlets
not necessarily in tourmaline; and
Quartz-cassiterite stringers and veinlets in tourmaline
About 0.5% to about 2% Sn
Over about 2% Sn
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As above, plus disseminated cassiterite in the
interstices of tourmaline
As above, plus wider and higher-grade quartz-cassiterite
Veinlets and veins or cassiterite as infill matrix of
breccia.
The Achmmach Tin Project comprises
mineralised envelopes or lodes, which
are known over a strike length exceeding
1.6km. Close-spaced drilling has enabled
the identification of east–west striking
subvertical tourmaline envelopes described
as “feeders” and gently to steeply north
dipping “branches”. The tourmaline
envelopes have been defined by drilling over
a vertical interval of approximately 600m.
The envelopes range from a few metres to
over 30m thick. The mineralised envelopes
appear to be relatively continuous in plan,
reflecting the continuity of the tourmaline
alteration mapped at the surface.
The occurrence and spatial distribution of
the cassiterite veinlets in the mineralised
envelopes dictate the distribution of tin,
which needs to be taken into account
during grade interpolation. In summary,
there are several features of the tin
mineralisation which are important to the
resource estimate:
• The mineralised envelopes are
primarily tourmaline-rich envelopes.
The envelopes contain the bulk of the
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