Cremated remains are the result of a human body being consumed by flames in a crematorium.
On average, an adult body results in 2-3kg of ashes, containing mostly the burned remains of bone (calcium phosphates), in addition to small amounts of minerals and salts.
Some other materials from implants or even coffin fittings, may also remain in melted lumps. Jewellery or spectacles can be worn by the deceased at the request of family, explaining why pieces of metal and glass can also be left behind too.
Many people now choose to collect cremated remains for subsequent scattering at a preferred location.