New High Grade Drill Targets and Porphyry Model Confirmed
- Five potential high-grade Zn breccia pipes confirmed by multi-element grab sampling in addition to the Zn breccia pipe discovery zone (single drill hole BRRC019 - 5m @ 8.0% Zn, 035% Pb from 32m (first and only hole into 2.2km long soil anomaly) at the Devon Cut Prospect (16th January 2018).
o All five new high-grade Zn breccia pipes targets (virgin - no historical workings) at Devon Cut returned high-grade Zn including and up to:
-- Target A - 9.47% Zn
-- Target B - 38.4% Zn
-- Target C - 48% Zn
-- Target D - 48.7% Zn
-- Target E - 35.43% Zn
o The potential high-grade Zn breccia pipes also returned:
-- Pb to 58.53% and 57.37%
-- Cu to 10.5%
- Historic workings at the Lightning Ridge Prospect returned very high-grade silver, lead and indium. Grab sampling results include:
o Ag to 1108 g/t, In (indium) to 515 ppm and Pb to 38.6%
- The Gossan East - Boom Boom Mancini mineralised trend extends over a strike of 5.4km. Results from virgin outcrop (no historical workings) includes:
o Pb to 34.96%, Zn to 5.06% and Cu to 5.34%
- At the Mt Brockman 2 Central Zn Prospect, widespread moderate grade Zn in sediments is associated with zincian smectite (sauconite).
o Zn values ranged from 1.23% to 2.29%
- Significant high-grade mineralisation has been delineated over a strike of 800m at the Mt Brockman 2 Prospect. Grab sample results include:
o Pb to 43.43%, Cu to 20.38%, Ag to 102 g/t and Zn to 3.59%
- A new potential high Zn breccia pipe (100m strike) has been discovered at the Mt Brockman 2 South Prospect. Very strong silica - sericite alteration up to 15m in width returned:
o Zn to 31.23%, Pb to 11.83% and Cu to 6.34%
- A new large barium-potassium-lead alteration system has been discovered 5km north northwest along strike from the Devon Cut Prospect. Barium potassic feldspar (hyalophane) occurs over a strike of 1.8km and up to 70m in width. 30 grab samples were collected.
o All anomalous with average >1% BaO.
o 9 samples reported > 5% BaO with a peak value of 8.16%.
o Pb averaged 2000ppm. Peak value of 1.44% Pb
- Access approvals are well advanced with the planned RC drilling scheduled for early August
Rumble's Technical Director, Mr Brett Keillor, said "The exploration potential for Braeside has been significantly enhanced with the recognition of large scale high level barium potassic feldspar alteration with elevated base metals.
Understanding regional zonation of metals is paramount in developing exploration vectors which will help Rumble find potential economic base metal deposits.
The discovery of barium rich potassic feldspar with strongly anomalous Pb, disseminated Zn in sediments and potential multiple high-grade sulphide (Zn rich) breccia pipes within major altered feeder structures, all support the porphyry vein/breccia pipe related - VMS model continuum that may ultimately lead to a camp scale base metal province."
Multi-element analysis (201 grab samples) have returned very high-grade zinc, lead, copper, silver, barium and indium assays. XRD (X Ray Diffraction) was completed on six samples to aid in determining mineral species.
The grab sampling and XRD analysis is aiding in prioritising first order RC drilling targets. Rumble is on track to commence drilling early August.
Grab Sampling Results
Multi-element assaying (201 grab samples) and XRD analysis focused mineralised trends determined by regional soil geochemistry with detailed pXRF in soil follow-up sampling. The soil geochemistry highlighted fifteen (15) base metal zones with up to twenty-three (23) targets/prospects (refer to announcement 5th June 2018 - Braeside Exploration Update - Multiple New Drill Targets).
The current grab sampling has only tested six (6) of these new targets and in addition, tested historic workings at the Lightning Ridge Prospect and defined an area of extensive Ba-K-Pb alteration at a new discovery known as Barium Ridge.
Devon Cut Prospect (see images 2 & 3 in link below)
High-grade base metal assays were confirmed from rock chip samples taken from all five potential Zn breccia pipes defined previously (announcement 5th June 2018). Additional to the discovery zone (single RC drill-hole BRRC019 returned 5m @ 8% Zn, 0.35% Pb from 32m), targets A to E (potential Zn breccia pipes) returned exceptionally high-grade Zn and/or Pb values in grab sampling over previously defined very high-grade Zn in soil geochemistry (pXRF). Results include:
Target A (200m strike)
Four (4) samples collected over virgin outcrop (no previous historical workings)
- Zn to 9.47%, Pb to 21.65%, Ag to 43 g/t and Au to 0.26 g/t
Target B (100m strike)
Five (5) samples collected over virgin outcrop (no previous historical workings)
- Zn to 38.4%, Cu to 10.5%, Pb to 3.18%, Ag to 76 g/t and Au to 0.11 g/t.
Target C (120m strike)
Seven (7) samples collected over virgin outcrop (no previous historical workings)
- Zn to 48%, Pb to 57.37%, Ag to 184 g/t and Au to 0.58 g/t
Target D (80m strike)
Two (2) samples collected over virgin outcrop (no previous historical workings)
- Zn to 48.7% and Pb to 2.65%.
Target E (200m strike)
Six (6) samples collected over virgin outcrop (no previous historical workings)
- Zn to 35.43%, Pb to 1.4% and Au to 0.57 g/t
Lightning Ridge Prospect (see images 2 & 4 in link below)
The Lightning Ridge Prospect lies close to the eastern boundary of E45/2032 and comprises of a series of shallow historic pits trending northwest over a strike of 250m. Geological observation indicates the mineralisation is a different style than the mineralised trends further to the west (wide pervasively altered fracture zones). Massive galena pods are associated with relatively narrow high-level quartz veining. A total of eight grab samples were collected (in-situ). Most samples returned very high-grade Pb (up to 38.6% Pb) however the silver content is very high returning up to 1108 g/t Ag. Indium was also very high with a peak value of 515 ppm In. Zn was relatively low (peak value of 1.63% Zn).
Gossan East- Boom Boom Mancini Zone (see images 2 & 4 in link below)
Grab sampling of three high-order base metal in soil targets (pXRF) has confirmed high-grade in-situ Zn and Pb mineralisation along the north-northwest trending Gossan East - Boom Boom Mancini alteration structure. Only fourteen (14) grab samples have been collected along 5.4 km of strike. Results include
Gossan East Prospect North Zone (250m strike)
Two (2) samples collected over virgin outcrop (no previous historical workings):
- Pb to 14.66%, Zn to 5.06% and Cu to 2.45%
Gossan East Prospect South Zone (200m strike)
Five (5) samples collected over virgin outcrop (no previous historical workings):
- Pb to 34.96%, Zn to 2.42%, Cu to 5.34% and Ag to 27.4 g/t
Boom Boom Mancini Prospect (1.5 km strike)
Six (6) samples collected over and along strike from some very small workings at the southern end of the Boom Boom Mancini trend returned strong Pb, Zn and Cu. Results include:
- Pb to 4.59%, Zn to 4.96% and Cu to 3.22%
- Further grab sampling (results pending) conducted along the 1.5km strike focused on recently discovered Zn carbonate gossans.
Mt Brockman 2 Central Zn, Mt Brockman 2 and Mt Brockman 2 South Prospects (see images 2 & 5 in link below)
Three zones of high-grade base metal mineralisation focused in the Mt Brockman 2 area have been confirmed by grab sampling (multi-element analysis).
Mt Brockman 2 Central Zn Prospect (400m strike)
Of potential significance is the Mt Brockman Central Zn Prospect where widespread moderate zinc mineralisation has been found within gently west dipping north-south striking fine grain volcaniclastics (siltstone). XRD (X Ray Diffraction) analysis has indicated disseminated zinc mineralisation is associated with zinc smectites (sauconite). Ten (10) grab samples were collected over 400m of strike. Five samples returned significant Zn anomalism ranging from 1.23% to 2.29% Zn. The rock chip samples were only slightly weathered.
Mt Brockman 2 (800m strike)
Over a strike of 800m, strong pervasive alteration trending north northwest returned high-grade base metals. A total of sixteen (16) grab samples were collected along strike with eight (8) samples reporting >10% Pb with a peak value of 43.43% Pb. Cu returned up to 20.38% with Ag to 102 g/t. Three (3) samples returned zinc in the range 2.78% - 3.59% Zn.
Mt Brockman 2 South Prospect (100m strike)
A potential new high grade Zn breccia pipe has been discovered over a strike of 100m at the southern end of the Mt Brockman 2 trend. Four (4) grab samples collected over very strong silica - sericite alteration (15m wide) returned zinc values of 31.24 % and 10.77% Zn. Other peak values include 11.83% Pb and 6.34% Cu.
Barium Ridge Target (see image 2 & 6 in link below)
A new zone of barium - potassium - lead anomalism associated with a large alteration system has been discovered approximately 5km north northwest along strike from the Devon Cut Prospect. The zone has a strike over 1.8km and is completely open. Alteration is up to 70m in width. Thirty (30) grab samples were collected from the alteration zone and 5 samples were analysed by XRD to confirm the mineral species related to the anomalism.
The XRD analysis has confirmed barium, potassium, lead and elevated rubidium are associated with feldspar. The feldspar belongs to the celsian - hyalophane group of relatively rare alkalic feldspars.
Multi-element analysis of the grab samples confirmed all 30 rock chips returned >1% BaO, with 9 samples returning >5% BaO. The peak value is 8.16% BaO. Potassium was high (average 5.8%) with a peak value of 9.51% K.
The average Pb content of all 30 samples is 2000ppm, with the peak value of 1.44% Pb. Rb was elevated with a peak value of 402ppm. Both the Pb and Rb report to the feldspar (hyalophane).
Exploration Potential and RC Drill Targeting of Current Prospects
Devon Cut Prospect (see image 3 in link below)
Five (5) new high-grade Zn breccia pipes have been inferred at Devon Cut based on the single RC drill-hole completed in Nov 2017 by Rumble (BRRC019 - 5m @ 8.0% Zn, 0.35% Pb from 32m within a broader zone of 30m @ 1.5% Zn from 28m). The single RC discovery drill-hole at Devon Cut was testing below a small historic mine (maximum depth of 8m). Geological observations defined multiple Zn gossans and characteristic oxidation textures/features indicative of Zn breccia pipes at surface with the workings and along strike. The discovery drill-hole and inferred breccia pipe is completely open. Based on the pXRF soil sampling and the latest very high-grade grab samples, the five new potential Zn breccia pipes along strike from the discovery have larger "signatures" and likely represent significant Zn mineralisation.
Rumble plans to test each potential new Zn breccia pipe with RC drilling. RC drilling is also planned to test the depth extension below the discovery hole (BRRC019) and immediately along strike to scope the size potential of the inferred breccia pipe.
Lightning Ridge Prospect (see image 4 in link below)
The mineralisation style at Lightning Ridge differs from the large alteration systems with base metals that lie further west. Mineralisation is podiform and associated with narrow quartz veining and there is only a thin selvage of alteration host within volcanics. The zone is northwest trending with a strike of 250m bounded by terminating faults. The high-grade silver (up to 1108 g/t) is consistent with grab samples returning 100 - 200 g/t Ag on average. The indium is also very high (up to 515 ppm) along with very high-grade Pb (up to 38.6%). The style is inferred to be a distal high-level base metal epizonal/epithermal vein (based on the high silver and indium).
Three RC drill sections have been planned to test the 250m strike zone.
Gossan East - Boom Boom Mancini Prospects (see image 4 in link below)
The mineralisation extends over a strike of 5.4km. Only fourteen (14) grab samples have been assayed with further sampling on-going. High-grade Pb and Cu with strongly anomalous Zn is associated with strike extensive silica-sericite altered zones with varying widths of 5 to 10m. Recent reconnaissance geological mapping and sampling subsequent to the current grab sampling results has identified significant Zn gossan outcrops along the Boom Boom Mancini trend. The style of target is considered to be similar to the Devon Cut Prospect.
Mt Brockman 2 Central Zn Prospect (see image 5 in link below)
Discovering disseminated Zn mineralisation in gently dipping volcaniclastics adjacent to north-south faults has highlighted the potential for porphyry related/VMS associated syngenetic to diagenetic sedimentary hosted base metal deposits. Elsewhere in the Braeside Project, disseminated Zn has been identified at the Bakers Dozen Prospect (see image 2 in link below) where pXRF soil geochemistry has outlined a 400m by 100m Zn anomaly (completely open). The Bakers Dozen Zn anomaly is hosted in siltstone over carbonate. The carbonate has no anomalism. The Zn values at Mt Brockman 2 Central Zinc Prospect are associated with Zn smectite (sauconite).
RC drilling is planned to test the Zn rich disseminated volcaniclastics in the primary zone. Subject to the mineralogy, if sauconite persists at depth, there is potential for non-sulphide supergene to hypogene Zn mineralisation styles.
Mt Brockman 2 Prospect (see image 5 in link below)
Predominately high-grade Pb occurs over a strike of 800m with moderate width silica - sericite alteration zones up to 6m in width. Later epigenetic quartz vein overprinting is relatively common with later deformation stages to the large alteration fracture/feeder zones. Late epigenetic mineralisation cross cutting the earlier feeder zones often upgrade galena into narrow high-grade quartz Pb veins and these veins were targeted by early prospectors. The epigenetic veins don't represent drill targets because of their narrow widths. Rumble is focusing the drilling on the wider alteration zones with strong Zn mineralisation.
Mt Brockman 2 South Prospect (see image 5 in link below)
A potential high grade Zn breccia pipe has been identified with very high-grade Zn (up to 31.24%) and intense silica - sericite alteration up to 15m in width. A single RC drill hole is planned with a deeper contingent hole if appropriate.
Barium Ridge Target (see image 6 in link below)
Deep RC drilling is planned to test the large barium potassic feldspar (hyalophane) alteration system. Known porphyry related and VMS deposits worldwide, often have barite capping massive base metal sulphides. In older moderately metamorphosed systems, barium rich potassic feldspar is often zonal to potential mineralisation.
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About Rumble Resources Ltd
Rumble Resources Limited (ASX:RTR) (FRA:20Z) is an Australian based exploration company, officially admitted to the ASX on the 1st July 2011. Rumble was established with the aim of adding significant value to its current gold and base metal assets and will continue to look at mineral acquisition opportunities both in Australia and abroad.
Rumble Resources Ltd