we know that diamonds did not form from coal because
Diamond A common misconception is that diamonds are formed from highly compressed coal. Coal is formed from buried prehistoric plants, and most diamonds that have been dated are far older than the first land plants. It is possible that diamonds can form from coal in subduction zones, but diamonds formed in this way are rare, and the carbon source is more likely carbonate rocks and organic carbon in sediments, rather than coal.[17][18]
Crater of Diamonds State Park Crater of Diamonds State Park is a 911-acre (369Â ha) Arkansas state park in Pike County, Arkansas, in the United States. The park features a 37.5-acre (15.2 ha) plowed field, the world's only diamond-bearing site accessible to the public. Diamonds have continuously been discovered in the field since 1906, including the Strawn-Wagner Diamond.[1] The site became a state park in 1972 after the Arkansas Department of Parks and Tourism purchased the site from the Arkansas Diamond Company and Ozark Diamond Mines Corporation, who had operated the site as a tourist attraction previously.[2]