Gulaga / Mt Dromedary Mining Heritage and Geology

Latitude -36.299908, Longitude150.030327

Located in the Eurobodalla Region of NSW, nearest town Central Tilba

Source: http://www.resources.nsw.gov.au/historical/mtdromedary-gold prime facts and Narooma 1:100,000 Geology sheet Explanatory_Notes.R00047930.

Link to Detailed Map

The forested ancient volcano that is Gulaga, (also known as Mt Dromedary), can be seen for miles around and protects, near its summit magnificent granite tors that are of great spiritual and cultural significance to the Yuin Aboriginal people of the South Coast of NSW.

The Guluga Volcano

There have been a number of prehistoric volcanic eruptions from Gulaga, the first occurring about 94 million years ago during the mid-Cretaceous period when dinosaurs still roamed the earth.

The ancient volcano complex covers about 40 sq km and has had a significant impact on the surrounding environment, with both Little Dromedary (Najanuka) to the east and Montague Island (Baranguba) formed through the volcano's activity. Gulaga, which is now 797m above sea level, would have originally been close to two thousand metres higher, and its foothills would have extended to Tuross Head. The mountain that you see today is basically the inner core of the original volcano. The volcano has been dormant since the Cretaceous period - which ended 65 million years ago.

Geology

Geologically, the mountain is known as the Mount Dromedary Igneous Complex and comprises a group of igneous and extrusive rocks belonging to the Shoshonite Association. These rocks have intruded Ordovician sediments to the east and west of the villages of Central Tilba and Tilba Tilba.

The main rock types present are monzonite and banatite (a rock of intermediate composition between quartz diorite and quartz monzonite) plus basic and andesitic lavas and tuffs. Monzonite forms the outer envelope to the banatite core of the main intrusive mass forming Mount Dromedary and there is strong evidence that they were emplaced by the vertical movement of magma creating a forceful intrusion into the surrounding Ordovician sediments. Dykes associated with the complex are common throughout the area: they are principally dolerite or a quartz feldspar rock.

Mining Heritage on Mt Dromedary

The presence of gold in the Mount Dromedary area was first noted in 1852 by the Rev. W.B. Clarke, who found alluvial gold along Dignams Creek. Subsequently, alluvial gold was located in many of the streams that drain the northern and southern slopes of Mount Dromedary.

Alluvial mining appears to have commenced about 1860, and a significant but unknown quantity of gold was recovered. In 1877, as a result of testing of alluvial ground high up on the slopes of Mount Dromedary itself, a number of narrow but rich gold-bearing vein deposits were found. These were worked largely over the period 1878-1920 for a yield of at least 603kg of gold. Further attempts to work the reefs were made in the late 1950s, but these proved unsuccessful. Total production from the field, both alluvial and reef, is not known, but is clearly well in excess of the recorded total of 603.05kg.

Primary gold mineralisation was represented by a series of vein deposits, the more important of which occurred near the crest of Mount Dromedary. These reefs were discovered in 1877 and comprised three main Lines of Lode; Mount Dromedary, North Dromedary and West Dromedary workings. Mineralisation occurred in the form of narrow, parallel pyrite-rich veins which trended in an east-west direction. Individual veins ranged in thickness to 45cm but averaged 15cm. Gold values were generally in excess of 30g/t.

The Mount Dromedary line of mineralisation was worked mainly by the Mount Dromedary Gold Mining Company during the period 1878-1910. It developed several tunnels into the mountain side, and stoped over a vertical interval of 231m. The lodes struck east-west and dipped vertically. In the upper levels the ore was partly oxidised, but at depth pyrite was an abundant constituent of the veins. It is estimated that total production from this line of mineralisation was 381.5kg gold. Production records indicate gold grades of the order of 30g/t.

The No. 5 tunnel of this mine was reopened in the late 1950s by Pacific Enterprises Limited, but no significant additional mineralisation was found. It is clear from available descriptions of the Mount Dromedary field that the primary gold mineralisation, although rich, was of limited tonnage potential.

Getting There

The NSW National Parks and Wildlife Service and the Gulaga Board of Management, consisting of a majority of Yuin Aboriginal owners, are responsible for the management of Gulaga National Park and encourage all visitors to enjoy the walk to the summit. This is approximately an 11km, 5 hour return trip that is steep in parts. The walk begins on the path behind Pam's General Store at the village of Tilba Tilba. There are two turn offs to Tilba Tilba from the Princes Highway, approximately 18 and 16kms south of Narooma. The first will take you through the heritage-listed village of Central Tilba and then on to Tilba Tilba which is three kilometres from the highway. The second turn off will take you straight to Tilba Tilba 1km from the highway.

If you are walking to the top take a light picnic and water to sustain you on the trip and also be prepared for dramatic changes in weather conditions. Enjoy the changes in the surrounding vegetation and birdlife as you go from the lowlands up the mountain, through pockets of misty rainforest to the summit.