Archaeologists have analysed residues from the internal surface of an ancient ceramic shard to discover it likely belonged to a 1,000-year-old hand grenade.
Four shards were uncovered in the Armenian Garden in Jerusalem – the site of an ancient royal palace – where researchers have unearthed a large number of relics dating back to the Byzantine Era.
They believe that a shard discovered there held the chemical ingredients for an explosive device “consistent with a medieval hand grenade”.
The Byzantine Empire was known to use early thermal weapons based on the invention of a combustible compound known as Greek fire – believed to have been based on naphtha and quicklime which was used to set fire to enemy ships.
Even before the use of gunpowder was pioneered in China, the Byzantine soldiers would pack the compound into stone, ceramic and later glass containers to create medieval grenades to target their enemies.
Evidence of one such grenade has been uncovered in research led by Professor Carney Matheson at Griffith University in Australia, and was published in the journal PLOS One.
Professor Matheson said: “These vessels have been reported during the time of the Crusades as grenades thrown against Crusader strongholds producing loud noises and bright flashes of light.”
The team analysed the residues on the inside of four shards to uncover what kind of compounds were present inside them, and these residues alongside the shape of the vessels helped indicate what they were used for.
One of them had residue indicating the vessel held oils, while the others held either medicinal contents or scented materials.
But the fourth shard was unique. It had very thick walls and no decoration and a sphero-conical shape – and the residue contained phosphorus, suggesting it contained historical incendiary materials.
According to the researchers the fourth shard was unique because – while the others contained valuable contents stored at the royal palace – it belonged to one of the explosive weapons used in the palace’s destruction.
“Some researchers had proposed the vessels were used as grenades and held black powder, an explosive invented in ancient China and known to have been introduced into the Middle East and Europe by the 13th century,” the professor added.
“It has been proposed that black powder may have been introduced to the Middle East earlier, as early as these vessels from the 9th-11th century – however, this research has shown that it is not black powder and likely a locally invented explosive material,” he added.