Bell metal metal used is a high-tin alloy of copper and tin with approximately a 4:1 ratio of copper to tin (78% copper, 22% tin). This is a much higher tin component than that used in statuary bronze. A range of percentages of tin content can vary from 20 to 26%, depending on the founder who has arrived empirically at their own alloy ratio. It has been found that increasing the tin content increases the decay time of the bell strike, thus making the bell more sonorous. Taking into consideration overall properties, such as tensile strength, hardness, wear resistance, cast quality, sound,
Sundown Tin and Copper Mine above the dams, leaching the metallic salts and having a strongly sulphurous smell. The Copper Mines are located about east of the furnace site, and consist an adit near the creek, and a series of 3 shafts along the line of the reef running roughly s-w to n-e over the crest of the ridge, and mullock associated with the shafts. The main shaft is a three-compartment shaft. There is a collapsed ore bin and shute, and some concrete machinery pads, but no other substantial above- ground remains. Sundown Tin and Copper Mine was listed on the Queensland Heritage Register on