CRAWLEY, AUSTRALIA—Rock art in Australia’s Western Desert has been dated for the first time with a new technique known as plasma oxidation, which prepares the samples for carbon dating. Jo McDonald and her team documented rock art sites in the eastern Pilbara at the request of traditional owners. When possible, they collected tiny samples of paint for testing. “We have discovered that this technique is a useful way of dating black paintings with charcoal in them,” McDonald told Phys.org. The paintings are between 2,000 and 3,000 years old.