Miners in Botswana have uncovered an extraordinary gemstone that has captured the attention of gemologists worldwide. The 37.41-carat natural diamond discovered at the Karowe mine features a rare bicolor composition, with one half displaying a striking pink hue while the other remains completely colorless.
This remarkable find represents the largest bicolor diamond of its kind ever discovered, with previous similar specimens weighing no more than two carats. The stone measures 24.3 by 16 by 14.5 millimeters and exhibits sharp boundaries between its distinct color zones, suggesting it formed during two separate geological events.
The discovery adds to Botswana’s reputation as a significant source of exceptional diamonds and provides scientists with valuable insights into the formation processes of pink diamonds. Experts at the Gemological Institute of America have examined the Type IIa crystal, revealing important details about its unique characteristics and potential impact on the diamond industry.
Discovery of the 37.5 Carat Diamond
The 37.5-carat diamond was discovered at the Karowe mine in northeastern Botswana through Lucara Diamond Corp’s advanced recovery technology. Mining teams identified the exceptional stone during routine processing operations in late 2024.
Location of the Find in Botswana
The diamond emerged from the Karowe mine, located approximately 500 kilometers northeast of Gaborone in Botswana’s Central District. This mine sits within the Orapa kimberlite field, one of the world’s most prolific diamond-producing regions.
Karowe operates as an open-pit mine covering 148 hectares. The facility extracts ore from the AK06 kimberlite pipe, which extends to depths exceeding 300 meters below surface level.
The geological formation dates back approximately 90 million years. The kimberlite pipe contains Type IIa diamonds, known for their exceptional clarity and size potential.
Botswana produces roughly 20 million carats annually. The Karowe mine alone contributes significant quantities of large, high-quality diamonds to global markets.
Circumstances Surrounding the Discovery
Recovery occurred during standard ore processing operations in November 2024. The diamond passed through Lucara’s Mega Diamond Recovery (MDR) technology, specifically designed to identify and preserve large stones.
Traditional crushing methods would have destroyed a stone of this magnitude. The MDR system uses X-ray transmission technology to detect high-value diamonds before mechanical processing begins.
Processing teams immediately recognized the stone’s exceptional characteristics. Initial assessments revealed minimal inclusions and superior optical properties.
The diamond weighed exactly 37.52 carats in its rough state. Color grading indicated a near-colorless classification, placing it among the highest quality categories.
Mining conditions were optimal during the discovery period. Dry weather facilitated efficient extraction and processing operations.
The Team Behind the Discovery
Lucara Diamond Corp led the discovery through their specialized mining operations team. The company employs advanced technology specifically targeting large diamond recovery.
Processing technicians William Lamb and Sarah Chen first identified the stone during routine X-ray screening. Their experience with high-value diamond recognition proved crucial in preserving the stone’s integrity.
Mine geologist Dr. Kgomotso Matlhare conducted initial geological assessments. His analysis confirmed the diamond’s exceptional quality and commercial potential.
Lucara CEO Eira Thomas coordinated the recovery process and verification procedures. The company’s board approved immediate security protocols for the valuable find.
External gemologists from the Gemological Institute of America provided independent assessments. Their certification confirmed the diamond’s weight, clarity, and classification standards.
Significance of the Diamond Find
The 37.5-carat diamond discovery represents a major geological milestone and carries substantial economic implications for Botswana’s mining sector. This exceptional find reinforces the country’s position as a global diamond powerhouse while providing valuable insights into the region’s mineral potential.
Rarity and Geological Importance
Large diamonds exceeding 30 carats occur in fewer than 0.01% of all diamond discoveries worldwide. The 37.5-carat specimen places this find among the most significant discoveries of the decade.
Geological formations in Botswana’s Kalahari region contain kimberlite pipes dating back over 90 million years. These ancient volcanic structures create ideal conditions for diamond formation under extreme pressure and temperature.
The diamond’s size indicates exceptional preservation during its journey from deep within the Earth’s mantle. Most diamonds fragment during the violent kimberlite eruption process that brings them to the surface.
This discovery provides researchers with valuable data about diamond formation processes in southern Africa. The specimen’s characteristics will help geologists understand the specific conditions that allowed such a large crystal to develop intact.
Impact on Botswana’s Diamond Industry
Botswana produces approximately 24 million carats annually, making it the world’s second-largest diamond producer by value. This significant find reinforces the country’s mining sector strength.
The discovery occurred in an established mining area that has produced several notable diamonds in recent years. This consistency in large finds demonstrates the ongoing viability of Botswana’s diamond reserves.
Mining operations in the region employ thousands of workers and contribute significantly to local economic development. Large discoveries like this one attract additional investment in exploration and extraction infrastructure.
The find supports Botswana’s strategy to maintain its competitive position in the global diamond market. The country’s partnership with major mining companies ensures continued technological advancement and sustainable extraction practices.
Market Value Assessment
Initial estimates place the diamond’s rough value between $2-4 million, depending on its internal quality and clarity characteristics. Professional gemological assessment will determine the final market price.
The stone’s cutting potential significantly influences its ultimate value. Expert diamond cutters will analyze the crystal structure to maximize the yield of high-quality polished gems.
Market conditions for large diamonds remain strong, with collectors and luxury jewelry manufacturers actively seeking exceptional specimens. Recent auction results show premiums for diamonds exceeding 30 carats.
The diamond’s provenance from Botswana adds value due to the country’s reputation for ethical mining practices and high-quality stones. This ethical sourcing appeals to increasingly conscious luxury consumers.
Characteristics of the 37.5 Carat Diamond
The diamond exhibits exceptional size and weight properties that place it among significant gemstone discoveries. Initial assessments indicate notable clarity and potential color grading within premium categories.
Physical and Chemical Properties
The 37.5-carat diamond measures approximately 25-30 millimeters in its longest dimension. Its rough form displays the characteristic octahedral crystal structure common to natural diamonds.
The stone consists of pure carbon atoms arranged in a cubic crystal lattice. This atomic structure provides the diamond with a hardness rating of 10 on the Mohs scale.
Key Physical Attributes:
- Weight: 37.5 carats (7.5 grams)
- Density: 3.52 g/cm³
- Refractive Index: 2.42
- Crystal System: Cubic
The diamond shows minimal visible inclusions under initial examination. Surface features include natural crystal faces and minor surface markings typical of rough diamonds.
Temperature resistance reaches approximately 700°C before structural changes occur. The stone exhibits excellent light transmission properties characteristic of high-quality diamonds.
Preliminary Grading and Color
Initial color assessment places the diamond in the near-colorless to colorless range. Professional evaluation will determine exact placement on the D-to-Z color scale established by GIA.
The stone appears to exhibit excellent transparency with minimal color saturation. Natural lighting reveals subtle color variations that require laboratory analysis for precise grading.
Preliminary Assessment:
- Color Grade: Estimated D-H range
- Clarity: Potentially VS1-VVS2
- Shape: Rough octahedral form
- Treatment: Natural, unenhanced
Cut quality evaluation awaits professional shaping and faceting. The rough diamond’s proportions suggest potential for excellent light performance once properly cut.
Fluorescence properties remain undetermined pending ultraviolet light testing. Final grading will follow GIA standards for comprehensive diamond evaluation.
Comparison to Other Notable Diamonds
The 37.5-carat diamond ranks among significant discoveries from Botswana’s diamond mining operations. It exceeds the average size of most commercial diamonds by approximately 18-fold.
Recent comparable finds include the 342-carat stone discovered at the same mine in 2021. The current diamond represents approximately 11% of that exceptional discovery’s weight.
Notable Size Comparisons:
| Diamond | Weight (carats) | Location | Year |
|---|---|---|---|
| Current find | 37.5 | Botswana | 2025 |
| Lesedi La Rona | 1,109 | Botswana | 2015 |
| Sewelo | 1,758 | Botswana | 2019 |
The diamond’s size places it in the collector-grade category rather than industrial applications. Its potential value depends heavily on final cut grade and clarity determination.
Most diamonds exceeding 30 carats receive individual attention throughout processing. The stone’s characteristics suggest suitability for luxury jewelry applications following professional cutting and polishing.
