Tungsten Mineral Resource

In December 2007 Paradigm announced an Inferred Mineral Resource at the White Rock prospect of 260,000 tonnes grading 0.7% tungsten oxide & 0.15% tin oxide based on 52 drill holes. This includes a high-grade 'black skarn' resource of 123,000 tonnes grading 1.15% WO3. Mineralisation is associated with magnetite-bearing skarn adjacent to granite.  Tungsten occurs as ferberite (FeWO4) and lesser scheelite (CaWO4) accompanied with abundant magnetite.

Preliminary metallurgical testing has produced tungsten oxide concentrates grading up to 68% in magnetic and gravity mineral processing tests.  Recoveries of tungsten are so far quite low (<50%), however further testwork will focus on refining the mineral processing flow sheet and improving recoveries. Testing of the magnetite indicates it could be suitable in the coal washing industry. 

Some of the best tungsten drill intercepts in the resource are:

• 12 metres @ 1.54% WO3 and 428 ppm Mo from 6m in WRP037
• 8 metres @ 1.80% WO3 and 138 ppm Mo from12m in WRP039
• 4 metres @ 1.0% WO3 and 176 ppm Mo from 23m in WRP040
• 11 metres @ 0.40% WO3 and 0.16% SnO2 from 30m in WRP026
• 3 metres @ 0.27% WO3 and 0.44% SnO2 from 23m in WRP016

Geology of White Rock

The White Rock Tungsten Deposit is a skarn replacement of limestone within a package of Silurian acid volcanic and sedimentary rocks on the margin of Devonian granite. The granite outcrops on two low-lying hills adjacent to the resource, with the skarn lying on the eastern flank of the granite. The skarn is poorly exposed, largely underlain by shallow alluvium. The tungsten-bearing skarn usually, but not always, contains significant quantities of magnetite (Figure 6).

The skarn replacement bodies form sub-horizontal lenses 1 to 10 metres wide adjacent to the eastern and southern contact of the granite (Figure 7). The mineralised skarn has replaced favourable rock units, mostly limestone and calcareous volcanic sediments. The skarn is characterised by the total replacement of limestone to an assemblage which includes magnetite, amphibole, biotite, pyroxene,  epidote, chlorite, ferberite (FeWO4), scheelite (CaWO4), molybdenite, pyrite, and pyrrhotite. Minor tn is believed to occur predominantly as cassiterite. 

Figure 6. White Rock drill map showing surface projection of skarn bodies