Greetings from Crater of Diamonds State Park! One of the easiest ways to find diamonds here is surface searching. Many of the large diamonds people hear about in the news are found on the surface of the plowed search area. As a result, people often have the misconception that most of our diamonds are found this way. While several diamonds are found on top of the ground, how does surface searching really work, how likely are you to find a diamond on the surface, and how can you maximize your chances of a surface find?
Finding diamonds by surface searching relies on the idea that diamonds are heavier than most other rocks and minerals at the park. We periodically plow the search area to loosen the diamond-bearing soil before a rainstorm. As rain falls on the field, it washes away dirt and uncovers large rocks, minerals, and diamonds near the surface.
Surface searching has paid off countless times over the years. Ray Schall, a regular visitor to the Crater of Diamonds for more than a decade, surface searched nearly every day. He recovered many diamonds during his years at the park, including a 6.07-carat white gem discovered in 1981.
Experience isn’t always necessary; first-time visitors often find diamonds while surface searching. In July 2013, a 12-year-old from Apex, NC found a 5.16-carat brown diamond after about ten minutes of surface searching the north side of the field. In June 2015, a visitor from Longmont, CO found an 8.52-carat white diamond near the southwest edge of the search area. In August 2019, a visitor from Bogata, TX picked up a 3.72-carat yellow diamond near the northeast boundary.
These are just a few examples of many surface diamonds found over the park’s long history. From 2016 to 2020, visitors discovered 237 diamonds while surface searching at the park, about ten percent of all diamonds registered during that time. While most diamonds found at the park weigh about one-quarter of a carat, the average diamond found on top of the ground weighs nearly two-thirds of a carat!
It’s important to know when surface searching is more fruitful to improve your chances of finding a diamond. More diamonds tend to be found on top of the ground during spring and late summer through early fall. Two factors make these seasons more successful: rain and sun.
Most surface diamonds are found on sunny days, two to three days after rainfall. Allowing time for the dirt to dry helps the diamond’s metallic luster stand out against dark diamond-bearing soil. After day three, the chances of finding a diamond on the surface drop steadily. Diamonds are rarely found by surface searching more than one week after it rains.
At least one inch of rainfall in a day typically increases the chances of finding diamonds on the surface. Significant rainfall can greatly improve the chance of surface finds. Park visitors found six diamonds on top of the ground after nearly seven inches of rain fell over a week in September 2018. After more than 13” of rain pelted the search area over four days in July 2019, visitors found seven surface diamonds in the days following.
Perhaps surprisingly, there is no apparent connection between plowing the search area and the frequency of surface finds. Visitors have found diamonds on top of the ground from days up to several weeks after the search area was last plowed.
Many people dream of finding their own diamond at Crater of Diamonds State Park, and surface searching is one of the easiest ways to search. Hopefully, these surface searching tips will help your dreams come true!