Largest Dental Caps

Spike; Calgary Zoo, Alberta, Canada; July 4, 2002.

The world's largest dental caps measure 50 cm (19 in) long, 13 cm (5 in) in diameter and weigh 13 kg (28 lb) each. They were fixed onto a pair of cracked tusks belonging to Spike, a resident Asian elephant, at the Calgary Zoo, Alberta, Canada during a 3 hour 30 minute operation on July 4, 2002. The stainless steel caps were designed and manufactured by the Southern Alberta Institute of Technology with metal donated by Corus Steel and adhesive by 3M (all Canada).

Source: Guinness World Records 2007

Largest Cut Diamond

Ran Gorenstein; Belgium; June 2004.

The world's largest cut diamond is an unnamed Fancy Black, containing small red diamond crystals. It weighs 555.55 carats and was polished into 55 facets over several years and completed in June 2004. The repetitive use of the number five is culturally significant in the Islamic world, and was inspired by Ran Gorenstein (Belgium), who also commissioned this creation.

Source: Guinness World Records 2007

Largest Carved Sapphire

Richard Sipe, Sr.; North Carolina, USA; March 19, 2005.

The largest carved sapphire is a multi-coloured (blue, gold, grey) polished rock that weighs 80,500 carats (16.1 kg, 35.49 lb). The sapphire was displayed during the annual Unifour Gem & Mineral & Jewellery Show at the Hickory Metro Convention, North Carolina, USA on March 19, 2005.

Source: Guinness World Records 2007

Largest Plate Inserted in Human Skull

Tom Thompson; Decatur, Georgia, USA; April 30, 1971.

Tom Thompson (USA) had a titanium plate measuring 15 x 11 cm (5.9 x 4.33 in) inserted into the left side of his head by neurosurgeons at DeKalb General Hospital, Decatur, Georgia, USA on April 30, 1971. The surgery took place after he had been struck by a car and pronounced dead on arrival at the local hospital.

Source: Guinness World Records 2007