Middle Island identifies second new gold deposit at Sandstone

Middle Island Resources Limited (ASX: MDI) has announced a highly positive update on the Phase 1 RC drilling program at its Sandstone gold project in the central goldfields of Western Australia.

The company reported that a new gold deposit has been defined at the McIntyre prospect within the Sandstone project. This is the second new Sandstone gold deposit announced in the past week.

MDI said that this deposit was defined by new, consistent, shallow drill intercepts including 24m at 1.66g/t, 23m at 1.40g/t, 11m at 1.39g/t and 18m at 1.35g/t Au.

The company said that the latest results derived from a further 12 holes (774m) of the 13,400m Phase 1 RC drilling program, address all results from the fourth of 14 targeted gold deposits and prospects.

MDI noted that there is a high likelihood that the McIntyre prospect will further complement the project’s mill recommissioning inventory.

It may be noted that McIntyre is one of a cluster of three proximal gold prospects, which include McClaren where substantial intercepts of 4m at 90.6g/t and 8m at 3.35g/t Au were reported recently.

The company said that the recently completed geological mapping indicates that the McIntyre and McClaren prospects are linked via a northeast trending corridor of more intense deformation and quartz veining.

MDI reported that further assay results are anticipated in the coming weeks.

Middle Island announced that it is well-funded to continue follow-up activities at McIntyre, McClaren and any further new discoveries at the Sandstone gold project.

Sandstone project

The Sandstone project and processing facility is situated 12km south of the township of Sandstone, ~400km northwest of Kalgoorlie, and located on a sealed highway between the mining towns of Mt Magnet and Leinster in the East Murchison Mineral Field of Western Australia.

The Sandstone gold project comprises two granted Mining Leases on which the processing plant is situated.

Significant prospects include Two Mile Hill, Shillington, Wirraminna, Goat Farm, Twin Shafts and Plum Pudding deposits. Other prospects include Ridge, McIntyre, McClaren, Old Town Well, Wirraminna Laterite (East & West), Davis, Tailings (South & East) prospects, and the G2 & G3 gravity targets.

McIntyre, McClaren, and the Ridge gold prospects are hosted within the southeast extension of the Shillington banded iron formation (BIF) package, located on granted Mining Lease M57/129, 2.5km from the Company’s Sandstone gold processing plant.

Phase 1 RC drill program at Sandstone

The company had recently completed a 13,400m, Phase 1, reverse circulation (RC) drilling program at Sandstone project. This drill program is one of four planned programs that collectively comprise a total 17,300m exploration and resource definition drilling campaign at the Sandstone gold project.

The Phase 1 RC program focussed on open pit targets, tested 14 gold deposits and prospects, all within 4km of the Company’s gold processing plant and the majority on existing Mining Leases.

Existing deposits: In the case of existing deposits, drilling was designed to variously extend Mineral Resources, reclassify Mineral Resources from Inferred to Indicated status, and/or upgrade JORC Code 2004 Mineral Resources to JORC Code 2012 compliance. These comprise the Two Mile Hill, Shillington, Wirraminna, Goat Farm, Twin Shafts, and Plum Pudding deposits.

Additional prospects: IThe company said that there were additional eight prospects assessed by Phase 1 RC drilling. These prospects are the ones which have had little or no drilling, but represent targets prioritised on the basis of their interpreted potential to generate open pit gold Mineral Resources. This includes the Ridge, McIntyre, McClaren, Old Town Well, Wirraminna Laterite (East & West), Davis, Tailings (South & East) prospects, and the G2 & G3 gravity targets.

High-grade drill results

The company announced that initial results have been derived from the Two Mile Hill deposit, and the McClaren, McIntyre, and Tailings East prospects for the Phase 1 RC drilling program.

McIntyre prospect

MDI reported that 12 holes (744m) of RC drilling were completed at the McIntyre gold prospect as part of a 13,400m Phase 1 RC drilling program comprising 172 holes in total.

Better RC drill intercepts from the McIntyre prospect include 24m at 1.66g/t (from surface in MSRC351), 23m at 1.40g/t (from 11m depth in MSRC352), 11m at 1.39g/t (from 25m depth in MSRC353) and 18m at 1.35g/t Au (from 32m depth in MSRC354).

Significant intercepts from McIntyre are as shown below.

The company noted that the McIntyre mineralised zone represents a potential new, very low strip ratio, open pit deposit that, along with the recently defined McClaren deposit, readily justifies further infill and extension drilling as part of the planned (circa 3,000m) Phase 2 RC drilling program.

MDI said that subject to infill drilling as part of the planned Phase 2 RC program, McIntyre and McClaren likely represent two new open pit deposits to complement the planned recommissioning inventory.

Opportunity for significant expansion

The company reported that the recently completed geological mapping of the proximal McIntyre, McClaren and Ridge prospects suggests that the former two are linked via a northeast-trending corridor of higher deformation, variously comprising intense, small, tight to isoclinal, shallow northeast plunging folds, accompanied by axial planar faulting and associated quartz veining.

MDI said that this deformation zone could represent the primary control on the distribution of gold mineralisation within the BIF units.

The company said that if this proves the case, the recent drilling orientation may be sub-parallel to the deformation zone, providing an opportunity to significantly laterally expand the mineralised zone in planned Phase 2 follow-up RC drilling. Equally, it also provides the opportunity to identify additional mineralisation along the deformation zone, beneath cover, between and beyond the McIntyre and McClaren deposits.

Next steps

The Company announced that it intends to infill drill the McIntyre prospect to the extent required to derive an Indicated Mineral Resource classification, which would allow these to be assessed and incorporated into the updated pre-feasibility study as Ore Reserves.

MDI said that Phase 1 RC drilling results for the nearby Ridge prospect are awaited to determine if associated gold mineralisation links up with the McIntyre and/or McClaren deposits.

Management comments

Middle Island Managing Director, Mr. Rick Yeates said: “The broad, consistent gold intercepts returned from Phase 1 RC drilling at the McIntyre prospect provide further exciting encouragement that the prospect may well prove to represent a second new, low strip ratio, open pit deposit to supplement the planned Sandstone mill recommissioning inventory.

This follows close on the heels of significant intercepts of 4m at 90.6g/t and 8m at 3.35g/t Au from the adjacent McClaren prospect as announced last week.

Recently completed geological mapping of the proximal McIntyre, McClaren and Ridge prospects, all of which are hosted in the Shillington BIF package, reveal a structural link between the McIntyre and McClaren prospects that offers opportunities for resource extensions to both.

The McIntyre and McClaren prospects lie within granted Mining Lease M57/129 and only 2.5km from the Company’s 100%-owned, 600ktpa gold processing plant.

The Directors look forward to sharing further Phase 1 RC drilling results with you as they are received and compiled. At this stage, the results of this program, coupled with the resources announced last week and the prevailing gold price, significantly heighten the prospect of a positive mill recommissioning decision.”

Written By Jonathan Norris
Jonathan is a founder of Mining.com.au and has been covering the resources industry since 2018. With over 17 years experience in print, broadcast and online media, Jonathan has seen first hand the transformative effect of online niche media.