Key Commodity: Copper, Gold, Silver
The Crystal Haven project embraces an area of approximately 50 square kilometres about 10 km south-west of the town of Almaden in North Queensland. The region has been an active producer of base and precious metals for 150 years, notably around the town of Chillagoe, which lies 25 km to the north-west of Almaden. A sealed road, a railway line, and a high-tension power line serve Almaden and Chillagoe and connect them to the port of Cairns. Cairns is approximately 200km to the east of the Project.
Although exposure is limited, a combination of the presence of old mine workings, geophysical surveys and remote sensing, and mapping and extensive sampling for geochemical determination, backed up by some drilling, has outlined the presence of a large and complex mineralised feature in the Crystal Haven project area, focussed on two, or possibly three, centres of porphyry intrusion with peripheral stockworks, breccias, and quartz veining, with indications that there may be a large parent body at depth below.
It is situated at the intersection of a major north to north-east-trending steeply dipping tectonic trend and a prominent north to north-west trending structural system known locally as the Palmerville Fault, part of a major lineament that can be traced through north Queensland for at least 2,000 kilometres and which is host to a number of the larger base metal and gold deposits.
The largest of the mineralised complexes at Crystal Haven is Dingo Hill, 800 m in diameter and comprising a number of breccia complexes, acid porphyries and dykes, and quartz veining, disposed in a circular pattern. Drill holes into this complex have returned intersections of gold, silver, and copper mineralisation of possible economic significance. There are two other complexes there, known as Quartz Needle Hill and 15-mile Hill that are also of interest and require systematic exploration. The mineralisation, alteration patterns, petrology, and geophysical responses are extremely similar to those that are found above major gold-copper deposits along the east coast of Australia and in the American Andean belt, such as Lake Cowal in NSW and Cascabel in Ecuador.
Investigations at Crystal Haven by a number of companies through the period 1984 to 2000, and exploration since then by the current proprietors of the Exploration Permits, have included mapping; soil, stream-sediment, and rock chip sampling, induced polarisation, magnetometric and radiometric geophysical surveys, analysis of spectral imaging, both core and non-core drilling to depths ranging from 10 metres to more than 400 metres, and some trenching. The paucity of outcrop, the size of the complex, and the deep weathering, have all combined to inhibit exploration, but have indicated that there are a number of targets that require more detailed exploration, particularly at depth.
- steep north-trending structures that extend to beyond 800 metres in depth which give strong geophysical responses that indicate extensive alteration and the possible presence of sulphide mineralisation;
- stocks or pipes of mineralised and brecciated porphyry;
- mineralised breccias peripheral to the stocks;
- sheeted vein systems;
- vein-hosted and breccia-hosted epithermal gold mineralisation and mesothermal base metal mineralisation at several localities; and
- copper-bearing porphyry style bodies lying at depth below the stocks of porphyry and breccia.
Drilling to date has successfully tested breccias and sheeted veins on Dingo Hill. Milled breccias cut by sheeted veins has produced drill intersections including 52m at 0.7g/t Au, 5g/t Ag & 0.6% Cu in pyrite and chalcopyrite mineralisation. Drilling has tested a 400m section of the 1.5km diameter coincidental geological, geochemical and geophysical anomaly. Drilling to date has defined a large resource target within the Crystal Haven Project area