Cockatoo Island has had a rich history of iron ore mining commencing in the 1950s. From 1951 to 2012, over 45Mt of ultra-high grade, low impurity direct shipping ore was mined and shipped. Pearl Gull Iron has mining title (M04/235) over a significant portion of Cockatoo Island and is targeting high grade iron mineralisation on Cockatoo Island. The Pearl Gull Iron exploration project on Cockatoo Island comprises three key areas being the Switch Pit, North Bay and the Magazine Pit:
The Company’s Project at Cockatoo Island provides Pearl Gull with not only high-grade exploration potential but also strategic positioning with respect to infrastructure required for both Pearl Gull’s planned operations, and the operations of third parties looking to conduct mining works or other operations on Cockatoo Island.
Reconnaissance work and review of previous Portman and Pluton reports has shown plans to mine at the eastern margin of the Seawall haematite body and into the footwall. The known geology extends east into Pearl Gull’s lease M04/235 and is referenced by Pearl Gull as the Switch Pit as it lies under an area historically used for a mining ramp with several switch backs to access the Seawall mine. Haematite mineralisation can be observed along strike from the historical Seawall mine on lease M04/448 and inferred onto lease M04/235. This inference is supported by outcropping mineralisation, previous drilling, and a historical block model. Recent observations show that the footwall stratigraphy has several haematite bands of variable thickness. The occurrence of the haematite bands in the footwall stratigraphy is typical of the footwall to the previously mined Seawall mine haematite mineralisation with the abundance of these haematite bands increasing toward the main thick massive Seawall haematite mineralisation. This is a high priority target for exploration.
The iron mineralisation within Switch Pit requires additional drilling to be reported on in accordance with JORC Code 2012 standards. However, the extension of known mineralisation in an area with outcropping rocks and surface sampling represents the potential for low geological risk direct shipping ore (DSO) tonnes for Pearl Gull Iron.
Work undertaken by Pearl Gull Iron at Cockatoo Island has identified the potential for high-grade structural repeats on the northern side of the island. The shallowest structural position of the prospective horizon repeating is in the northeast part of the Pearl Gull Iron’s tenure, and it is this area that will be the focus of initial exploration work. There are several areas of outcropping high-grade haematite which support this interpretation. This type of repeat is present at the nearby Koolan Island (owned by Mount Gibson Iron Ltd) with Acacia, Barramundi, Eastern and Mullet pits in the central and northern parts of that island along strike equivalent positions of the stratigraphy that Pearl Gull Iron is targeting at Cockatoo Island.
The Magazine Pit area is located in the southeast part of the tenement package. It is underlain by Magazine Schist (stratigraphically above the Cockatoo Formation). However, within the Magazine Schist there are haematite rich bands with quartzite. Previous explorers have examined the area (via completing 25 RC holes) for beneficiation grade iron ore (20-40% Fe). The company is planning to drill confirmatory holes in this area.