It is a unique insight to the ground beneath the gold city of Charters Towers, passed down from an era before computer modelling.
A 1930s plate glass model of the ore bodies and workings of the area has been taken out of storage and is set to be restored to its former glory.
The broken model consists of a box with slots for sheets of glass carrying fine markings to build a layered 3D picture of the old underground mines and gold reefs.
Charters Towers resident Garry Watson is among the Zara Clark Museum volunteers working to restore the display, originally commissioned by Gold Mines of Australia to encourage investors, before the outbreak of World War II put an end to their plans.
“This plate glass model is a unique master plan of the Charters Towers reefing system,” Mr Watson said.
“It was meticulously created by a mining company in the 1930s to provide an accurate perspective of how the reef and mine shafts relate underground.
“After being stored in Brisbane for many decades it was reconstructed for display here in the 1970s.”
Mr Watson said the model was held in the assay office attached to the Stock Exchange Arcade complex for some time before being shifted to the National Trust-run Zara Clark Museum last year.
There it has been slowly patched up – with new backlights fitted, glass sheets cleaned and reassembled. Mr Watson said two surface sheets and 12 plates bearing underground reef details were missing.
The North Queensland branch of The AusIMM has agreed to contribute towards the restoration efforts, including purchase of new glass plates.
It is planned to display a computer monitor with a rotating 3D graphical model of the Charters Towers orebodies and mine workings alongside plate glass model to demonstrate advancements in 3D visualisation.