Welcome to the observation area of the Stawell Gold Mine. From this vantage point you can see the tunnel which heads underground where golden treaures await.... You can also see some rocks on display which you will need to look a little more closely at.
GOLD
Gold is a chemical element with symbol Au (from Latin: aurum) and atomic number 79. In its purest form, it is a bright, slightly reddish yellow, dense, soft, malleable, and ductile metal. Chemically, gold is a transition metal and group 11 element. It is one of the least reactive chemical elements and is solid under standard conditions. Gold often occurs in free elemental (native) form, as nuggets or grains, in rocks, in veins, and in alluvial deposits. It occurs in a solid solution series with the native element silver (as electrum) and also naturally alloyed with copper and palladium. Less commonly, it occurs in minerals as gold compounds, often with tellutium (gold tellurides).
Gold's atomic number of 79 makes it one of the higher numbered, naturally occurring elements. It is thought to have been produced in supernova nucleosynthesis, from the collision of neutron stars, and to have been present in the dust from which the Solar System formed. Because the Earth was molten when it was formed, almost all of the gold present in the early Earth probably sank into the planetary core. Therefore, most of the gold that is present today in the Earth's crust and mantle is thought to have been delivered to Earth later, by asteroid impacts during the Late Heavy Bombardment, about 4 billion years ago.
Gold was discovered in the region back in the 1850's and this area has been extensively mined since. In fact between 1981 and 2010 2,000,000 (yes 2 million) ounces of gold have been produced here at the Stawell Gold Mine.
Logging the Cache
Your task is to answer a few questions by looking at the rocks on display. You may need to so some further research to come up with the answers:
1. Looking at the Central Lode Ore piece of rock tell me how many grams of gold you can find per tonne in a rock like this? What is your estimate of the value of this rock given this gold content? Explain your reasoning.
2. Looking at the Central Lode Ore piece of rock describe it to me (colour, size texture etc). Compare to the Basalt Contact Ore. Why are they different?
3. Looking at the Basalt Contact Ore piece of rock tell me how many grams of gold you can find per tonne in a rock like this? What is your estimate of the value of this rock given this gold content? Explain your reasoning.
4. Looking at the Basalt (Waste Rock) tell me how far beneath sea water that this was formed and how long ago? How is this rock different from the Ore rocks?
Once you complete the Earthcache requirements you can post your find without delay, as per the guidelines. You will also need to verify your find by sending me an email providing answers to the questions. This can be through the message centre or via gemmasiemensma@gmail.com
Thanks for visiting this Earthcache. I hope you enjoy it.