Dave Hole discovered something extraordinary while digging for gold in Maryborough Regional Park near Melbourne, Australia, in 2015. With the help of a metal detector, he found a heavy and reddish rock lying on a yellow clay.
Extremely Hard And Heavy Rock
Hole was hoping to find a gold nugget inside the rock because the object was heavier than it looked. Maryborough is also in the Goldfields region, where significant gold mining occurred in the 19th century.
Despite numerous attempts, however, Hole failed to open the rock. He used a rock saw, a drill, an angle grinder, an acid, and even a sledgehammer, but nothing made the object crack.
He nonetheless kept the object. It was years later that he found out that the rock was more valuable than he thought. It is something rarer than gold.
4.6 Billion-Year-Old Meteorite
Intrigued by his find, Hole contacted the Melbourne Museum to find out what it really was. It did not take long for museum geologists Dermot Henry and Bill Birch to realize the object is something from out of this world.
"It had this sculpted, dimpled look to it," Henry said. "That's formed when they come through the atmosphere, they are melting on the outside, and the atmosphere sculpts them."
Testing confirmed that Hole's gold nugget was in fact a 4.6 billion-year-old meteorite and has been called the Maryborough meteorite.
The space rock is so heavy because unlike rocks on Earth, it is packed with very dense forms of nickel and iron.
Silver Raindrops From Birth Of The Solar System
The gemologists used a super-hard diamond saw to slice off the edge of the rock which revealed little silver raindrops. These were once droplets of silicate minerals that crystallized from the super-hot cloud of gas that formed the solar system.
Analysis also revealed that the rock lacks weathering, suggesting that it had been on Earth for less than 200 years.
"There is no evidence for any shock-inducing event and the meteorite shows incipient weathering in the form of thin iron-oxide mantles around the Fe-Ni grains. A terrestrial age of less than 1,000 years is estimated from C14 dating," the gemologists reported in the Proceedings of the Royal Society of Victoria on July 17.