Mary Valley Manganese Project

Eclipse Metals Ltd holds 31sqkm of manganese exploration terrain in south-eastern Queensland, in the Mary Valley district about 16km to the southwest of the regional centre of Gympie.

Queensland Manganese

Mary Valley Manganese:

Eclipse Metals Ltd holds 31sqkm of manganese exploration terrain in south-eastern Queensland, in the Mary Valley district about 16km to the southwest of the regional centre of Gympie. The granted tenements lie partly within the Amamoor State Forest, which has been largely invaded by exotic weeds and undergrowth and large sections have been cleared and replaced with plantations of hoop pine. Access to site is via local sealed roads thence to drill locations via existing forestry tracks.


The largest mine on the tenements was at Amamoor No.1 Manganese Deposit (19,630t @ 51% Mn). The mine opened in 1920 and operated intermittently until 1961.

A total of 31,477 tonnes of manganese ore has been mined from within the Mary Valley tenements, with manganese grades ranging from 42% to 51% Mn. Limits of the deposit have not been defined either along strike or at depth.

Historical assays have also indicated that the Mn, Fe, Si and P levels are all within direct shipping ore parameters which further confirm the economic potential for stand-alone mining operations within the Mary Valley manganese area.


Results from two diamond drilling programs conducted by Eclipse Metals on the historic Amamoor manganese mine-site indicate that bulk low-grade mining procedures could be utilised to develop and mine this manganese deposit to provide mill-feed for a beneficiation plant to produce a marketable, high-grade product.

Best intersections from the Amamoor prospect included:

  • 2m @ 46.3% MnO from 7.8m in Hole ADD006
  • 4m @ 26.3% MnO from 14.9m in Hole ADD007
  • 6m@ 7.00%MnO from 2.0m in Hole ADD002B

Interpretation of these results and gravity survey data highlight the open nature of the high-grade mineralisation, and that multiple lodes exist in close proximity in at least one area at Amamoor, where the mineralisation presents as steeply-dipping, lenticular-shaped fault-controlled zones (refer cross-section Figure 11).

Angled hole ADD002B, sited toward the southwestern end of the prospect in an area of elevated gravity values intersected 10.6m of manganese mineralisation with an average grade of 7.0% MnO from 2m depth, dipping flatly at 15° to the east, in line with the company’s geological expectation for that area. While this intersection was of lower grade, the company will investigate the opportunity to identify higher grade mineralisation in the vicinity. The company believes that this intersection, together with occurrence of float and sub-outcropping manganese mineralisation over a wide area to the west and south-west of historical workings, strongly supports the potential for substantial extensions of mineralisation in the southern area at Amamoor.


Holes ADD006 and ADD007, drilled to target depth extensions in an historically mined area, intersected layered-to-massive manganese mineralisation over much of their length.

These intersections, along with surface evidence of interpreted mineralisation, indicate the potential for mineable widths of both low-grade mineralisation which may be beneficiated, and high-grade DSO manganese mineralisation previously identified in the project area.

AMAMOOR ADD006 ADD007 Interp cross section


A summary of manganese production near the Mary Valley Project is shown below, where Amamoor No.1 produced 19,630t @ 51% Mn


Working of Mined Areas

Years of Production

Ore production (tonnes)

Donaldson’s Deposit

22.86m long x  9.14m wide x 2.74m deep

1949, 1960

25t @ 46% Mn, 15% silica

Mooloo T.O Prospect

15.24m long x 2.13m wide x


42% Mn, 11.6% silica, 5.8% Iron oxide

Mt Mooloo Prospect

Trench 1 and 2: 13.71m long, 2.74m deep


81t @ 50.3% Mn, 1.9% silica, 7.4% Iron oxide

Trench 2: 15.24m long, 2.13m wide x 1.52m deep

Robert’s Prospect

6.40m long x 4.26m wide x 3.04m deep


15t @ 38.6% Mn

Dagun Prospect

6.1m long x  2.4m deep

1921, 1949

100t @ 48% Mn, 5% silica

Eel Creek

15.24m long x 2.13m wide

1949, 1951, 1960

234t @ 50% Mn, 6% silica

38t @ 46% Mn, 15% silica

Mt Walli

1937-38, 1959

700t @ 48% Mn, 9% silica

45.72m long x  3.35m deep

20t @ 40% Mn,20% silica

Amamoor No.2



515t@ Unknown

Zachariah Creek



16t @ 40% Mn, 10% silica

Skying Creek

152.0m long x 4.57m wide


2,457t @ 45% Mn, 19% silica


44.2m long x 3.65m wide x 19.81m deep

1918-19, 1958-60

8,893t @ 46% Mn, 22% silica

Amamoor No.1

274.0m long x 27.43m wide x 21.33m deep

1920, 1960

19,630t @ 51% Mn, 10% silica


31,477 t of High Grade Mn