HIGHLIGHTS
- Systematic sampling and assaying of drill core from the Central
Mineralised Zone at Serra Pelada has yielded platinum (up to 299 g/t),
palladium (up to 387 g/t) rhodium (up to 7.7 g/t) and iridium (up to
4.9 g/t), grades among the highest on record
- High grade PGE-gold intervals include FD-072:
7.88 metres @ 406.4 g/t gold, 98.4 g/t platinum , 115.7 g/t palladium,
2.74g/t rhodium, 1.52g/t iridium, 0.19g/t ruthenium and 0.03g/t osmium
including
1.87 metres @ 1431.3 g/t gold, 248 g/t platinum , 321.4 g/t palladium,
6.50 g/t rhodium, 4.21g/t iridium, 0.39g/t ruthenium and 0.10g/t osmium
- Platinum to rhodium ratio varies systematically with the gold to platinum
ratio, ranging from around 10:1 to over 40:1. In this range, rhodium
values will contribute significantly to the value of high PGE subzones at
Serra Pelada
- The assay data indicate high PGE subzones in more southerly parts of the
Central Mineralised Zone, where Colossus has only conducted limited
drilling to date and also the possible continuity of a high Au-PGE subzone
over 200 metres strike length.
DETAILS
Core samples from seven
drill-holes representing 128 metres of down-hole intersections
in the Central Mineralised zone were fire assayed for gold, platinum,
palladium, rhodium, iridium, ruthenium and osmium by PGE specialist Genalysis Ltd., Perth, Australia. These data are
the first systematic assays for the full PGE suite at Serra Pelada. A summary of core sampling, sample types,
analytical methods and QA/QC measures is given in TECHNICAL
INFORMATION, below.
Some extraordinarily high gold
and PGE assays were encountered over metre core lengths. These values
include platinum (up to 299 g/t), palladium (up to 387 g/t) rhodium
(up to 7.7 g/t) and iridium (up to 4.9 g/t), grades among the highest
on record.
Significant assays for
continuous intervals of Au-PGE mineralisation are presented in the
following table:
----------------------------------------------------------------------------
Inter- Gold Plat- Palla- Ruth-
From val(i) (ii) inum dium Rhodium Iridium enium Osmium
Drillhole (metres) (metres) g/t g/t g/t g/t g/t g/t g/t
----------------------------------------------------------------------------
FD-072 251.79 13.71 204.5 58.6 69.2 1.61 0.90 0.11 0.02
including 251.79 7.88 406.4 98.4 115.7 2.74 1.52 0.19 0.03
256.85 1.87 1431 248 321.4 6.50 4.21 0.39 0.10
----------------------------------------------------------------------------
less
than
FD-058A 230.04 1.91 169.1 13.64 18.99 0.43 0.59 0.03 0.02
less
than
and 277.58 8.93 9.62 6.11 6.68 0.21 0.12 0.02 0.02
----------------------------------------------------------------------------
less
than
FD-062 273.74 3.06 115.9 35.57 46.12 1.33 0.75 0.11 0.02
----------------------------------------------------------------------------
less
than
FD-104 274.4 7.50 27.73 9.68 6.62 0.41 0.14 0.03 0.02
----------------------------------------------------------------------------
(i) True thickness not known
(ii) Gold and PGE fire assays using NiS collector material
These drill-holes are from
more southerly sections of the Central Mineralised Zone, where
Colossus has undertaken limited drilling to date. The assayed
intervals apparently represent high-PGE subzones that warrant further
drilling to establish continuity. Platinum/palladium ratios are also
higher than expected from historical data for these subzones. The
high Au-PGE subzone in FD-072 may prove to be continuous with those
so far encountered in Colossus Phase I drilling in the upper and
outer fold hinge, up to 200 metres to the northeast.
Over the entire assay dataset
platinum /rhodium ratios vary from around 10 to over 40. In this range
rhodium values will contribute significantly to the value of high PGE
subzones at Serra Pelada and less so to high Au/PGE subzones,
although the latter (eg. FD-062) may exhibit higher iridium values.
Colossus will undertake further systematic PGE assays over a broader
geographic range and to clarify the distribution of PGE in different
alteration types in the Central-and other mineralised zones.
Vic Wall, Colossus President,
comments "The Au-PGE assay results would be extraordinary
anywhere other than Serra Pelada. Colossus' work continues to add
value to the Serra Pelada treasure chest, demonstrating that PGE's
will contribute significantly to the worth of this remarkable
deposit."
ABOUT RHODIUM AND IRIDIUM
Rhodium is a rare,
silvery-white, hard transition metal and a member of the platinum
group. Rhodium is found in platinum ores and is used in alloys with
platinum and as a catalyst. (Source: Wikipedia). After trading as
high as US$10,000 per ounce in 2008, rhodium is presently trades at
approximately US$1300 per ounce.
Iridium is a very hard,
brittle, silvery-white transition metal of the platinum group, is the
second densest element and is the most corrosion-resistant metal,
even at temperatures as high as 2000 degrees C (Source: Wikipedia). Iridium
currently trades at approximately US$425 per ounce.
TECHNICAL INFORMATION
Sampling of historical Vale
core (by Colossus personnel) and sample preparation (by SGS GEOSOL
LABORATORIES LTDA., Belo Horizonte) were carried out under strict
protocols as recommended in the 43-101 Technical Report on Serra
Pelada and independently by Pitard (2007). After photographing and
logging, nominal 1
metre intervals of remaining half core were
completely removed yielding samples of up to 2 to 3 kilogram
mass. Where core recoveries were low, intervals were composited to
yield approximately 1 kilogram minimum sample masses.
A range of sample types were
submitted to Genalysis Ltd., Perth Laboratory. Where possible these
included splits of rejects from coarse crushes, non-subsampled and
previously sampled pulps, Duplicates, blanks and certified gold-PGE
reference materials were inserted in the sample train by Colossus
personnel prior to secure shipping to SGS. Genalysis inserted other
Au and PGE reference materials in all batches.
Genalysis performed screen
fire assays (AAS & MS finishes, Pb collecter) on the pulverised
rejects (greater than 95% passing 106 microns) from the crushed
(greater than 95% passing 1.7mm), dried samples. Pulps were
re-homogenized and fire-assayed for Au-Pt-Pd utilising 50 g or 25 g aliquots and Pb
collectors and also for Au and the complete PGE suite utilising 25g
aliquots and NiS collector materials. Additional blanks and
duplicates were inserted in the assay streams by Genalysis and
replicate assays were performed every twenty samples. Genalysis
dispatched assay certificate originals directly to Resource and
Exploration Mapping Ltd. an independent Company which manages
Colossus' database.
The Genalysis assay results
for blanks, duplicates and replicates were generally satisfactory. However
unacceptably high Au-(Pt-Pd) values were noted in some quartz washes
of pulveriser-homogenizer vessels. These values appear to have
resulted from over-grinding and smearing of noble metal particles on
vessel walls. Genalysis advises that some Au-Pt-Pd assays should be
regarded as low due to these effects, but mass balances and
additional check assays indicate that effects on grade and possible
carryover between samples were generally within analytical
uncertainties.
Genalysis assay results of
certified Au-PGE reference materials were generally within accepted
ranges for these materials. The results from different methods of
fire assays were consistent within assay uncertainties. For the
internal consistency assays utilised in this release were 25gm sample
fire assays utilising NiS collector for Au and the PGE-suite. Screen
fire and multi-element assays performed on the sample batches will be
the subject of a later release.
Dr. Vic Wall, President of
Colossus Minerals and qualified person under National Instrument
43-101, is responsible for this release and has verified the contents
disclosed.
About Colossus:
Colossus is an exploration and
development Company focused on mineral resource properties in Brazil.
The Company is currently focusing its efforts on the high grade
gold-platinum-palladium Serra Pelada project in Para State, Brazil. Between
1980 and 1986 Serra Pelada was host to the largest precious metals
rush in Latin American history. Coverage by 60 Minutes of this famous
mining rush can be viewed at the following link: www.sixtyminutes.ninemsn.com.au/article.aspx?id=299887. In addition, the Company has another
drill-ready gold project, Natividade, in the State of Tocantins,
Central Brazil.