ROBUST RESOURCES LIMITED 
By
ASX: ROL 18th September 2013
• Discovery of extensive VMS1-style gold, silver and rich base metals at Batu
Perak enhanced by recent assay results
o LWD 357 intersected 12.28% base metals and 5.04 g/t AuEq2 over 6m
o Potential strike >2 km; 500m tested by drilling to date with 100% success rate
• Stratabound VMS deposit intersected in all 9 holes drilled at Batu Perak
• Higher grade VMS deposit maybe amenable to open pit mining and flotation
o Opportunity for enhanced metal recoveries
o Metallurgical testwork has commenced on larger-scale flotation project
• Two rigs dedicated to drilling Batu Perak; six on other targets
Robust Resources Limited (ASX: ROL) is pleased to advise that recent exploration activity at the Batu Perak prospect at the company's Romang Island project is enhancing project development options based on what is now very likely to be a large VMS-style discovery.
Drilling has already indicated that the Batu Perak VMS-style mineralisation is laterally extensive and geologically continuous. To date, nine holes have been drilled and each hole has intersected the VMS horizon and significant mineralisation. Figure 1 shows a cross section in which the mineralised zone is interpreted to be continuous for over 400 metres. Recent drilling results on this section are LWD 340 and LWD 349. The mineralisation is open-ended.
Figure 2 shows a parallel cross section situated 160 metres northwest of Figure 1. Again, the mineralised zone is consistent and open ended. Included in this section is the recent result from LWD 357:
o 21m at 2.04 g/t gold equivalent2 & 4.69% combined base metals from 22m
(0.74 g/t Au, 69 g/t Ag, 0.19% Cu, 1.85% Pb, 2.64% Zn) including:
o 6m at 5.04 g/t gold equivalent & 12.28% combined base metals from 22m
(1.65 g/t Au, 179 g/t Ag, 0.44% Cu, 4.33% Pb, 7.52% Zn)
Drill hole LWD 362, also on this section, has been completed and the VMS mineralised zone is present. Assay results are expected in coming weeks. Figure 3 shows the plan view of the Batu Perak exploration target with the dimensions indicated. Table 2 at the end of this report gives detailed results of the three new holes.
Exploration Target
Based on exploration to date, which includes drilling results, surface indications from geology, geochemistry and geophysics, it is possible to portray an exploration target at Batu Perak. The stratabound VMS mineralised body has been intersected in all of nine holes drilled at Batu Perak. The table below displays the values and averages (length weighted where appropriate).
Table 1: Table of Batu Perak VMS intersections
Reasonable assumptions of the lateral dimensions for the exploration target are 350m x 2,000m (see Figure
3), and a bulk density of 2.5 tonnes per cubic metres is assumed. Based on these parameters, an
exploration target can be approximated at between 8 - 12 million tonnes of between 5% and 7%
combined base metals (Pb+Zn+Cu), between 1 and 2 g/t gold and between 60 and 80 g/t silver:
approximately 400 to 600 thousand ounces of gold, 20 to 30 million ounces of silver, and 1 to 1.5 billion pounds of base metals. This potential quantity is conceptual in nature and only limited drilling has yet been done. There has been insufficient exploration to estimate a mineral resource and there remains uncertainty that further exploration will result in the estimation of a mineral resource.
Robust is currently drilling the targets within the Lakuwahi Caldera with 8 rigs. Two rigs are dedicated to drilling the Batu Perak VMS exploration target. It is estimated that a preliminary mineral resource estimate for Batu Perak will be announced within 6 months but full assessment of the target may take in the order of
12 months.
The above exploration target does not include any stringer sulphide or stockwork mineralisation that nearly always occurs beneath the main exhalative horizon. It is possible that some parts of this stringer zone can be mined economically.
Other considerations that may enhance the potential of the exploration target, are the postulated existence of hydrothermal feeder or vent structures (geophysical evidence exists) and topographic undulations in the sea-floor base of the caldera, at the time the mineral-bearing fluids were active. A thickening of the sulphide deposits should occur at or near to the main vent structures. Thickening of mineralisation is also possible at considerable distances (hundreds of metres) in topographic bowl-shaped depressions in the ancient sea bed. More drilling should determine if either of these scenarios are a reality.
Context of discovery
Robust has been exploring the Lakuwahi Caldera with great success since late 2008. Initial exploration efforts were directed towards outcropping mineralisation, and for that reason, most of the promising early results were of oxide and transition gold and silver. During the initial months it was also recognised that significant deposits of polymetallic mineralisation had been discovered and that they had potential to be many times larger than the near-surface gold-silver oxide. It was realised that economic potential of the polymetallic deposits would be greatly enhanced if a consistent high-grade orebody could be discovered. Due to the extensive nature of the targets, it was clear that a considerable investment of time, skill and drilling would be needed to properly define the potential of the Lakuwahi Caldera. That effort still continues and the rate of discovery remains exceptionally high.
The emphasis and early exploration success for near-surface oxide ore also influenced the company's thinking on the development route for Romang Island. Major effort was put into technical studies on potential heap leach options. Excellent gold recoveries and acceptable silver recoveries were obtained from column
leach tests and the heap leach scenario, in combination with an initial high-grade direct shipping manganese oxide, remains a possible development path.
In 2012 Robust made a significant discovery of a higher-grade gold and silver-rich exhalative polymetallic mineralisation at Batu Perak. The geology of the Batu Perak discovery is distinctly different from the majority of earlier base metal intersections at Lakuwahi. The Batu Perak high-grade mineralisation occurs at the contact between the lower Lakuwahi Volcanic rocks and the younger Upper Volcanics and sedimentary rock units. The style of mineralisation is considered to be exhalative: base and precious metals, along with abundant barium deposited on, or just below, the ancient sea bed. The closest analogy is perhaps the rich Kuroko-type deposits in Japan but there are many other ancient and modern deposits, some of great economic importance, which are also considered to be exhalative in origin. Collectively they are known as Volcanogenic Massive Sulphide or VMS deposits.
The discovery of higher grade precious metals-rich polymetallic deposits means there is potential to move straight to a larger project with possibly more efficient processes for the recovery of all metals within the Lakuwahi deposits.
Robust's Managing Director Mr Gary Lewis commented: "The discovery of the Batu Perak VMS system is significant for the company. It is clear that Romang Island is shaping up to be a project of considerably large scale, and as such, it may be more economical to pursue the processing route of a larger flotation project. The oxide gold-silver ore, which was previously earmarked for a heap leach project could be absorbed into this flotation processing operation. Metallurgical testwork has already commenced.
"Our current exploration efforts are now focused on supporting this development option and they are being undertaken in conjunction with extensive test work and project development activities. This development planning is also being supported by environmental investigations which we are undertaking to transition from an exploration licence to a mining licence. This is now a priority.
"As well as our exploration and development activities for a larger flotation project, scoping studies are also underway on the high-grade manganese project at Romang Island, and the results are looking positive for early commercialisation. Recent marketing efforts in China have been positive, and this manganese project could be an early source of revenue for Robust.
"We look forward to updating shareholders on our exploration and development efforts in the coming months and with our current rate of drilling we anticipate a strong and positive news flow."
Table 2: Recent drilling results from Batu Perak
About Robust
Robust Resources is a multi-commodity resource company engaged in the exploration and development of precious and base metals in Indonesia, the Kyrgyz Republic and the Philippines. It holds a 70.5% managing interest in the Polymetallic and Manganese Romang Island projects in Indonesia, which incorporates an interim Indicated and Inferred JORC mineral resource estimate of 592 thousand ounces of gold, 27.7 million ounces of silver, 95 million pounds of copper, 697 million pounds of lead and 678 million pounds of zinc (resource table; see website: www.robustresources.com.au). Since the completion of the JORC resource estimate in January 2012, Robust has completed additional drilling totaling over 14,000 metres and over 150 holes with consistent positive results. Robust holds 80% of the Andash project in the Kyrgyz Republic with JORC resource estimate of 679,023oz Au plus
77,308lb Cu and JORC Reserves Estimate of 539,730oz Au plus 63,486lb Cu. Robust recently signed an agreement to earn-in a
70% interest in Bashkol copper-gold project in the Kyrgyz Republic. Robust's dual focus is to become a significant low cost precious and base metal producer on Romang Island and Andash as well as continuing its positive record of new discoveries from its portfolio of exploration properties. Robust trades on the Australian Securities Exchange (ASX) under the symbol ROL.
Robust Resources is now on Twitter. Please click on the link provided to follow: https://twitter.com/RobustResources
*** ENDS ***
For further information please contact: Gary Lewis - Managing Director on +61 2 8259 4799
Competent Persons Statements
The information in this announcement that relates to Exploration Targets and Exploration Results is based on data compiled by John Levings BSc, a Competent Person who is a Fellow of The Australasian Institute of Mining and Metallurgy. Mr Levings is a director of the Company. Mr Levings has sufficient experience, which is relevant to the style of mineralisation and type of deposit under consideration and to the activity, which is being undertaking to qualify as a Competent Person as defined in the 2012 Edition of 'Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves'. Mr Levings consents to the inclusion in the announcement of the matters based on his information in the form and context in which it appears.
1. VMS = Volcanic Massive Sulphide = Volcanogenic Massive Sulphide (see description page 3 of text)
2. AuEq = Gold Equivalent = gold assay + (silver assay / 53) where the number 53 represents the ratio where 53 g/t Ag = 1g/t Au. This ratio was calculated and rounded to the nearest whole integer from the average of the 24 months of Financial Year 2011 from July 2011 to June 2013 taken from published World Bank Commodity Price Data http://siteresources.worldbank.org/INTPROSPECTS/Resources/334934-
1304428586133/pink_data_m.xlsx. The metal prices thus used in the calculation are the average Gold price of USD $1638.39 per ounce and average Silver price of USD $31.05 per ounce.
72.0m @ 0.96 g/t AuEq & 1.9% BM incl 34.0m @ 1.26 g/t AuEq & 2.6% BM and incl 9m @ 2.83 g/t AuEq & 4.3% BM and incl 8m @ 1.86 g/t AuEq & 1.7% BM
22.7m@ 1.37 g/t AuEq & 2.9% BM
BATU PERAK- CROSS SECTION C- D
68m@ 0.6 gftAuEq & 2.1% BM
incl 4.0m @ 2.13 gft AuEq & 3.2% BM
incl 6.0m @ 2.56 g/t AuEq & 4.2% BM 26.3m@ 1.6 gftAuEq & 3.5% BM
incl 7.2m@ 3.64 gft AuEq & 9.4% BM 4.8m @ 2.62 gft AuEq & 9.6% BM
c .... !V D
p v v '-J '-J
Unconsolidated
300m Basin Fil/
LIMESTONE (+/-Manganese) UPPER VOLCANICS
open v BARITE-rich Horizon
.. (yellow)
250m v
v v
v v v v v v v v v v v v v
v v v v v v
v LUKAWAHI
200m 25m @ 2.1 gft AuEq & 2.0% BM VOLCANICS
incl 13.7m@ 3.1 gft AuEq & 2.6% BM r; 50 100
v v v
v v v v v v v v v
v / v
v v v v m) v v
v
150m
8m@ 1.1 gftAuEq v v v v v v v v v v v v v v v v
4.1% BM v v v v v v v v v v v v v v v v
(incl.1.25% Cu) v v v v v v v v v v v v v v v v v v v v "v
Drillhole trace
AuEq = Gold Equivalent
Au + (Ag/53)
BM = Base metals
(Cu + Pb + Zn)
S Veinlet and disseminated Base Metal Mineralisation (>1% BMs)
High-Grade Gold-Silver-Base Metal mineralisation associated with horizon of anomalous barite mineralisation separating Upper Volcanics and LukawahiVolcanics.
Gold-Silver Mineralisation (0.5 g/t eut off)
Figure 1: Batu Perak cross section showing mineralisation continuous over 400 metres and open ended. Note the consistency of the geology and the development of stringer and breccia mineralisation in the footwall of the high-grade exalative horizon.BM = combined base metals (Pb+Zn+Cu)
21m@ 2.04 g/tAuEq & 4.7% BM
incl 6m@ 5.04 g/t AuEq & 12.3% BM
BATU PERAK- CROSS SECTION E- F
E RESULTS
86.6m @ 0.6 g/t AuEq & 0.9% BM
incl 4.2m @ 2.8 g/t AuEq & 9.2% BM
9'
30.0m @ 0.8 g/t AuEq & 1.3% BM
incl 5.1m@ 2.5 g/t AuEq & 7.1% BM
F
AWAITED ....., ....., ....., .....,
300m Unconsolidated
Basin Fil/
LIMESTONE (+/ - Manganese)
v UPPER VOLCANICS
v ? BARITE-rich Horizon
v v (yellow)
250m
v // v v v v v v v v v / v v v v v v
/
v v v v v v
./ v v v v v v v
v v v v v
'1)'.... --
v v v v v v v
LUKAWAHI
200m v VOLCANICS
ov v vso v v 100 v v v v v v v v v v v v
v = v v v v v v v v v v v v
(m)
"" ""i
.i...
Veinlet and disseminated Base Metal Mineralisation (>1% BMs) High-Grade Gold-Silver-Base Metal mineralisation associated
Drillhole trace
AuEq = Gold Equivalent
Au + (Ag/53) BM = Base metals (Cu + Pb + Zn)
with horizon of anomalous barite mineralisation separating
Upper Volcanics and Lukawahi Volcanics.
Gold-Silver Mineralisation (0.5 g/t cut off)
Figure 2:This section is located 160 metres "along strike" to the northwest of the section if Figure 1. lt presents a strikingly consistent pattern of mineralisation- again open ended. The recent results far hole LWD 357 are shown.LWD 362 has been completed and the mineralised rocks were intersected in the hole- assay results are awaited. BM = combined base metals (Pb+Zn+Cu)
Soil Silver Equivalent
Contours
=Ag + (Au * 53) g/t
L >16ppm
D >8ppm
>4ppm
BATU PERAK FLATSNon-Outcropping Basin with Potential far Volcanogenic Sulphide Base Metals + Au/Ag
Figure 3:Map of the Batu Perak VMS exploration target zone.northwest- southeast strike potential is at least 2 Km metres and mineralisation is demonstated to beat least 400 metres wide.lt should be noted that no drillhole into the Batu Perak and Purple Heart targets has failed intersect mineralisation.
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