Geelong Keys

The Geelong Keys were a set of five keys discovered in 1847 at Limeburners Point, on the southern shore of Corio Bay, near Geelong, Victoria, Australia. In September of that year, Charles La Trobe, Superintendent of the Port Phillip District and a keen amateur geologist, was examining marine deposits revealed by excavations associated with lime production in the area. A worker showed him two of a set of five keys he claimed to have found the day before, in a layer of shells 15 feet (4.6 m) down an excavation for a lime kiln, which was about 40 feet (12 m) from the shoreline. La Trobe was fascinated by the find and believed, from their appearance, that the keys were between 100 and 150 years old (~1700-1750 AD).

Since the 1802 expedition of Matthew Flinders is the earliest proven European presence in the vicinity, writer Kenneth McIntyre has suggested the keys may have originated with some earlier European explorers of the region, possibly the Portuguese. McIntyre has connected the discovery of the Geelong Keys with the presence of the so-called Mahogany Ship, further west on Victoria's Shipwreck Coast, claiming that it could be another possible relic of early Portuguese exploration.

The editor of the Geelong Advertiser at the time, James Harrison, noted that metal objects were often embedded in new diggings to detect the leaching of payable metal. For instance, a copper oxide coating on the keys would suggest the presence of copper. Ronald Gunn, a friend of La Trobe, told the Royal Society of Victoria in September 1849 that he had gone to Geelong to investigate the discovery. On questioning the limeburner he found that the keys had not, in fact, been dug out of the shell layer but were found with shells at the bottom of the pit. It was only assumed that they had fallen from the upper layer. In practice they could have fallen from any layer, including the top of the excavation.

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