Renison undertook a large amount of metallurgy and recovery test work. The tin occurs as the mineral cassiterite and is also within goethite rich rock, which was given the local name of gillianite. The two types of tin mineralogy are contained in about 50% proportions. The cassiterite is generally of fine grain size and requires sophisticated gravity recovery technology. The tin in the gillianite is acid soluble.

The Renison work showed that the South Basin hosted three significant ironstone lenses, containing the majority of the cassiterite mineralisation. In 1976, Renison, estimated the tonnes and grade for this mineralisation to amount to 1 million tonnes grading 0.7 to 0.9 % tin. Renison observed that the Pinnacles deposit (also held by CTM) was a similar type of deposit. Renison withdrew from the project in 1978.

Otter continued desk-top pre-feasibility studies on the Gillian prospect for the next 19 years. Otter particularly looked at treatment options for low-grade tin, including the gillianite mineralisation. In 1980, a consultant metallurgy group recommended consideration of tin fuming recovery processes to produce tin metal. This technique was in its infancy in 1980.

In 1983, Otter estimated a resource of 2.3 million tonnes grading 0.84% tin for all the defined mineralisation at the Gillian Project.

Strike Exploration Pty Ltd (“Strike”) farmed into the property in 1995. Using the past drilling data, geological consultants Rockcombe Pty Ltd, on behalf of Strike, estimated a resource of 1.8 million tonnes grading between 0.54 and 0.69% tin. The Strike report was prepared by John Gallo (1981).

Strike sold the Gillian tenement to Tin Australia NL in 1998. In 1999, John Sainsbury, a current director of CTM, estimated the Gillian cassiterite tin mineralisation to amount to 500 000 tonnes grading 1.0% tin, above a lower cut-off of 0.5% tin and using a nominal bulk density of 3.0 g/cc. This was included in the Tin Australia prospectus of 1999.

In 2005, Tin Australia sold the Gillian tenement to Bluestone Tin Ltd which in 2006 merged with Metals Exploration Ltd to form Metals X Ltd (“Metals X"). Consultant mineral valuation firm, Behre Dolbear Australia Pty Limited, was retained to prepare a valuation of the Gillian deposit (along with the other mineral properties from both companies: “Review of Assets of Metals Exploration Limited and Bluestone Tin Limited”). This valuation, in October 2006, observed the 2004 JORC Code, and estimated a Gillian resource of 2.3 million tonnes grading 0.84% tin, which was used for valuation purposes: this is the Otter resource from 1983.

VWPL classifies all of the above resource estimates as indicated under the JORC Code, but notes the following:

• These indicated resources are global estimates from which probable reserves cannot be estimated, at this stage.
• More drilling and test work is needed to increase confidence in mineralisation limits and continuity, mean grades, bulk density and metallurgical issues.
• The John Sainsbury estimate of 500 000 tonnes grading 1.0% tin in cassiterite is conservative.

Conclusions - Mineralisation Potential and Future Work

The Gillian deposit is reasonably well defined but there is scope to drill for increases in tonnes along strike, in both directions and at depth. The skarn in the South Basin is steeply dipping and depth has not been ascertained. The skarn in the North Basin seems to be shallower and depth limited.

The Gillian mineralisation was considered difficult to treat because of the fine cassiterite as well as the tin contained in gillianite. The technology was not available in the 1970s and 1980s for acceptable recovery from this type of mineralisation. The technology is now available using fine grinding and recovery with centrifugal jigs. Tin fuming methods for the treatment of low-grade concentrates is another option to be considered. (Metals X is testing and planning to commercially develop tin fuming processes for fine concentrates from the Renison mine tailings).

Gillian is a moderate size deposit of tin mineralisation. Future drilling is required to confirm shape, tonnes and grade to current JORC Code Indicated Mineral Resource and Probable Ore Reserve categories and to obtain samples for the determination of treatment recovery. The technological improvements are now available that may well make this a profitable venture at current prices.

A detailed magnetic survey will be flown to better locate the magnetic minerals alteration and identify new skarn target areas.

It is quite likely that the Gillian deposit, which contains about 18 000 tonnes of tin metal of which at least 5000 tonnes are in cassiterite, might form the key resource for CTM’s quest to establish a hard-rock tin operation.