Jack Cohen may refer to:

• Jack Cohen (Tesco) (1898–1979), British businessman
• Jack Cohen (politician) (1886–1965), British Conservative Party politician, Member of Parliament for Liverpool Fairfield 1918–1931
• Jack Cohen (scientist), (1933 - )British biologist and special effects consultant

References

• SDNHM The Nature of Diamonds: Facts About Diamonds Most diamonds are over three billion years old, two-thirds the age of the Earth. There are a few "youngsters," though, which are only 100 million years old.
• Howstuffworks "Carbon and Kimberlite" The surface area of diamond-bearing kimberlite pipes ranges from 2 to 146 These are diamonds that originate in kimberlite pipes, but get moved by
• DIAMOND (Carbon) Diamond is the ultimate gemstone, having few weaknesses and many strengths. It is well known that Diamond is the hardest substance found in nature,
• Engagement Rings and Diamonds from Diamond Exchange Ltd Ideal Cut Diamonds with Hearts and Arrows and Diamond Engagement rings at Diamondexchange prices.
• Diamonds - Mahalo Lots of tips on how to buy diamonds and engagement rings. Also has a shopping directory of diamond stores conveniently categorizd by various diamond jewelry
• Loose Diamonds, Engagement Rings and Diamond Jewelry | Tutorial Tutorials buying loose diamonds and engagement rings from diamond jewelry stores, resources and free diamond prices and engagement ring quotes.
• Amazon.com: Diamonds - Materials Online shopping for Diamonds Materials from a great selection of Jewelry & Watches; Merchandising Features & more at everyday low prices.
• Diamonds Diamonds are crystalline carbon and the hardest known substance. This photo shows diamonds from the Argyle Mine in northern Western Australia.
• Howstuffworks "How Diamonds Work" Diamonds are some of the hardest and most valuable materials found on the Earth. Learn about diamonds and find out how diamonds are formed.