Superglue may be a modern convenience, but it might not be such a recent invention. Using Stone Age materials, South Africa-based researchers have recreated a glue that they suspect people at that time made to hold their tools together.
Red ochre dye once thought by archaeologists to only serve a decorative or symbolic purpose in present-day South Africa 70,000 years ago, may have actually been the magic ingredient in a Stone Age recipe for natural superglue.
The natural red pigment is rich in iron, and was added to the gum of acacia trees to create an adhesive, a blend that the new research shows was less brittle and more durable than glue made solely from acacia gum. Researcher Lyn Wadley said, “We discovered that when we used ochre, the glue is much more robust, and the stone tool doesn’t come off the shaft.”
How Stone Age humans devised the trick, however, is still a mystery—and quite an impressive one: Wadley said, “They couldn’t possibly have known about chemical pH or iron content.”