Amidst a heated debate surrounding the determination of diamond origin, the issue of traceability and its implications for the industry has taken global centre stage. In light of the G7 summit and the increasing emphasis on traceability protocols, the question of how to accurately identify the geographic origin of diamonds has become a contentious topic. In this article, we delve into the ongoing controversies and explore the challenges and potential limitations of trace element analysis in determining the origin of diamonds. By examining the current landscape, we aim to shed light on the complexities surrounding this issue and propose alternative approaches to ensure transparency and ethical practices within the diamond industry. The determination of a diamond’s geographic origin through trace elements analysis has long been regarded as a promising avenue for gemmologists. However, it is essential to critically assess the feasibility and limitations of this approach.
The Illusive Distinctiveness of Trace Elements
The premise of utilising trace elements as ‘chemical fingerprints’ to identify the origin of gemstones has yielded fruitful results in the case of rubies and sapphires. These gemstones, with their higher trace element concentrations, lend themselves more readily to analysis and differentiation. However, diamonds present a different scenario altogether.
Diamonds: Elusive and Homogeneous
The primary obstacle in trace element analysis of diamonds lies in their remarkably low concentrations of trace elements. Unlike other gemstones, diamonds are composed predominantly of carbon atoms, resulting in a highly pure structure that hampers the inclusion of other elements during crystal growth. The minute quantities of trace elements present in diamonds fall within the parts per billion or even parts per trillion range. This poses a significant challenge in terms of accurate measurement, as well as the cost and time associated with specialised techniques such as laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS).
Overlapping Characteristics: Geological Realities
The geological processes and conditions involved in diamond formation exhibit striking similarities across different regions worldwide. Diamonds are typically born deep within the Earth’s mantle, within peridotite and eclogite rocks. The mineral inclusions found in diamonds, which often serve as indicators of their origin, are commonly observed in deposits globally. These shared characteristics reflect the analogous growth environments experienced by diamonds, irrespective of their source.
Unveiling the Methodological Hurdles
Achieving diamond origin determination through trace element analysis necessitates fulfilling three crucial requirements: distinct characteristics between origins, a comprehensive comparative database, and the practicality of routine measurement. Unfortunately, existing data and analysis fall short of meeting these requirements.
The collection of sufficient data points from diamonds of known origin is an arduous task that demands extensive resources and time-consuming analysis. Additionally, the current high-tech methods employed for trace element measurement are neither cost-effective nor practical for routine laboratory services. These limitations cast further doubts on the viability of trace element analysis as a reliable means of diamond origin determination.
Embracing the Complexity: A Shift in Focus
It is crucial to approach the topic of diamond origin determination with a balanced perspective that acknowledges the inherent limitations of trace element analysis. This approach ensures transparency and traceability within the diamond supply chain, fostering consumer confidence. While trace element analysis has shown promise in determining the origin of certain gemstones, its application to diamonds poses significant challenges. The low concentrations of trace elements, overlapping geological characteristics, and methodological limitations all contribute to the contested accuracy of diamond origin determination. Rather than striving for an elusive goal, it is more pragmatic to focus on maintaining accurate provenance information and fostering ethical practices within the diamond industry.
As the industry grapples with the contentious debate over diamond origin determination, it is essential to critically evaluate the potential limitations and challenges associated with trace element analysis. While the prospect of using trace elements as chemical fingerprints initially seemed promising, diamonds’ unique nature of diamonds, low trace element concentrations, and shared geological characteristics have presented significant obstacles. Instead of solely relying on this methodology, the focus should shift towards preserving and documenting country-of-origin and mine-of-origin information from the time of mining.
By embracing transparency and traceability within the diamond supply chain, we can address consumer concerns, promote ethical practices, and ensure the long-term sustainability of the industry. As discussions around traceability protocols heat up, industry stakeholders must collaborate to find effective solutions that balance the complexities of diamond origin determination with the need for transparent sourcing.
Leanne Kemp
CEO, Everledger
everledger.io
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