Blister Dam and New Mexico – Au
The Blister Dam project is located 65km northwest of Kalgoorlie-Boulder on granted Exploration and Prospecting licenses forming a semi-contiguous land package of over 20km of strike. The tenure is located on and adjacent to the geologically and economically significant Zuleika and Kunnanalling shears which hosts some of the highest grade underground mines currently in production in the Eastern goldfields including the Kundana and Frogs Leg mines. Several targets occur on the well-known Zuleika Shear, where historic drill holes have intersected two distinct gold mineralisation styles; thin high grade quartz veins and shears zones hosting broad widths (>40m) of disseminated low grade gold.
During 2017, 21 targets were identified at Blister Dam. These were based on interpreted structures, geological contacts, historic drilling and geochemical signature. Nine of these prospects were drill tested with 46 Reverse Circulation (“RC”) holes drilled for 4,120m in 2017 to an average depth of 90m. Subsequently in 2018, Intermin conducted follow up drilling at the more promising prospects including Atlantic, Argo and Seven Seas. First pass drilling was also conducted at three additional targets including the historical Chadwin workings, Loran and Atlantic South. An Induced Polarisation (“IP”) survey was also completed in 2017 to define several new targets.
The bulk of the 2018 drilling was directed at the Atlantic prospect and followed up to the 2016 drilling. Significant 2016 results included:
- 17m @ 1.01g/t Au from 59m (BDRC1603)
- 4m @ 3.13g/t Au from 80m (BDRC1604)
- 4m @ 1.30g/t Au from 56m (BDRC1602)
In addition, historical drilling had identified broad sequences of low grade, shear hosted mineralisation (0.4-0.9 g/t Au) which was confirmed in the 2018 drilling including:
- 56m @ 0.60g/t Au from 54m (BOH 0.57 g/t Au from 109-110m, BDRC18029)
- 53m @ 0.69g/t Au from 60m (BDRC18028)
- 68m @ 0.82g/t Au from 56m (BDRC18008)
Within these low grade zones, there are a number of discrete higher grade shoots. The best of these was BDA153 (14m @ 2.90g/t Au from 62m). Wide spaced drilling centred on BDA153 returned no significant results to date.
To try and capture the cross structure thought responsible for this mineralisation, the drill grid was reduced to 20m enabling improved modelling of the ore zone. Better results included:
- 7m @ 1.54g/t Au from 59m & 14m @ 1.09g/t Au from 79m (BDRC18008 – Atlantic)
- 9m @ 1.56g/t Au from 69m (BDRC18024)
- 10m @ 1.26g/t Au from 58m (BDRC18026)
- 1m @ 4.08g/t Au from 54m, 8m @ 1.27g/t Au from 66m & 4m @ 1.16g/t Au from 93m (BDRC18029)
The second priority target at Blister Dam is Argo. Argo was discovered in 2017 whilst testing some nearby historic holes and soil anomalies. The best first pass results from 2017 included 4m @ 5.03g/t Au from 46m (BDRC17050) and 10m @ 1.02g/t Au from 20m (BDRC17009).
Step back drilling on a 20m x 40m pattern discovered that strong mineralisation extends to 70m vertical depth as shown in Figures 5 and 6. Significant results at Argo included:
- 6m @ 5.97g/t Au from 66m (BDRC18001, visible gold panned)
- 12m @ 4.03g/t Au from 16m (BDRC18003)*
- 8m @ 1.41g/t Au from 8m (BDRC18017)*
- 8m @ 1.05g/t Au from 80m (BDRC18013)*
* denotes 4m composites.
The mineralisation has now increased from 40m to 140m and, potentially, remains open to the northwest. Anomalous, untested soils are noted immediately SE of Argo. Further drilling, including diamond, is scheduled for Argo in 2019.
Field reconnaissance around the Argo area confirmed the prospectivity of several proposed 2017 targets. These included the historic Chadwin workings and Drabbco/Argosy workings 450m west of Argo. The Drabbco/Argosy workings were briefly tested in 2017 by BDRC17029 (1m @ 2.15 g/t Au). This result was followed up by 3 additional holes in 2018, however no significant mineralisation was intercepted.
Chadwin is located 3km SE and down strike of the small Magdala open cut mine (~4,300 oz, 1993). At Chadwin, a line of small workings is sited on some thin, quartz veins dipping steeply to the south west. Four holes retested the Chadwin workings and depth extensions with mixed success. Significant results included:
- 4m @ 2.48g/t Au from 56m (BDRC18040)
- 1m @ 4.75g/t Au from 32m (BDRC18038)
The fourth target tested in the Chadwin-Argo area is now known as the Loran prospect. Loran sits about 400m north east of the Chadwin workings. It is a new discovery, but more importantly Loran exhibits more definitive geological control on the gold mineralisation than other areas studied at Blister Dam. Two holes tested the soil anomaly with BDRC1801 returning 5m @ 1.47g/t Au from 66m. The ore zone is visual, and sits on a sheared basalt/ultramafic contact. A hilly outcrop of recently recognised, massive porphyritic basalt (“cat rock”) separates Chadwin from Loran. Soil anomalies on adjacent flanks are noted.