Diamonds are some of the most popular and fascinating gemstones in the world. Here are 10 diamond facts that you may not have known. Diamonds are the hardest natural substance on earth: This means that they cannot be scratched by any other substance, including other diamonds. Diamonds come in different colors: While most diamonds are colorless, diamonds can also be found in a range of colors, including yellow, brown, pink, blue, and green. The largest diamond ever discovered weighed over 3,000 carats: The Cullinan diamond, discovered in South Africa in 1905, weighed 3,106 carats. Diamonds were first discovered in India over 2,500 years ago: India was the only source of…