A 998-Carat Diamond Was Discovered In Botswana

A 998-carat rough diamond was discovered in Botswana in the Karowe Diamond Mine owned and operated by Lucara Diamond, a mining company that specializes in unearthing large diamonds. It could be the fourth largest gem quality diamond ever discovered.

The diamond, which measures 67x49x45mm, was recovered from a direct milling of ore sourced from an area in the open pit mine that has recently resulted in discoveries of diamonds weighing 273, 105, 83, 73, and 69 carats. Lucara announced the discovery Tuesday night.

Eira Thomas and Catherine McLeod-Seltzer who founded Lucara Diamond invested in untested equipment and technology for the Karowe mine specifically designed to unearth exceptionally large diamonds. The 998-carat diamond represents the second 500-plus carat diamond recovered from the mine in 2020. Those two diamonds are among 31 diamonds of greater than 100 carats, with 10 of those diamonds greater than 200 carats, the mine has produced this year. The two largest are the 549-carat “Sethunya,” and the most recent 998-carat discovery, which has yet to be named.

Lucara is working with HB Antwerp, a high-quality diamond cutting and polishing specialist, to evaluate the next steps in maximizing the value of the rare large stone. The two have an agreement to work together for all diamonds greater than 10.8 carats that Lucara discovers.

“To recover two 500-plus carat diamonds in 10 months along with the many other high quality diamonds across all the size ranges is a testament to the unique aspect of the resource at Karowe and the mine’s ability to recover these large and rare diamonds,” Thomas said in a statement. “Operations at Karowe have continued through 2020 and operational challenges, due to Covid-19 restrictions, have been met with professionalism by the team. We look forward to a safe finish to 2020 and continued success at Karowe as we remain focussed on strong operations to ensure maximum resource performance.”

Lucara and the Karowe mine have an unprecedented track record of unearthing exceptionally large diamonds that stretches back at least five years. The discoveries include:

* The 1,758-carat “Sewelô,” unearthed in April 2019. It is the second largest gem-quality rough diamond ever unearthed. The stone was purchased by French luxury brand, Louis Vuitton, which is working with HB Antwerp to polish and cut the diamond.

* The 1,109-carat “Lesedi La Rona,” unearthed in November 2015. It was purchased in September 2017 by renowned diamond jeweler, Laurence Graff.

The world’s largest gem-quality diamond ever unearthed is the storied 3,106-carat Cullinan found in South Africa in 1905. At the rate Lucara is finding large diamonds, it may have a shot at catching the Cullinan.

Jeweller confidence revives on festive demand hopes for gold

The jewellery demand was impacted by recurring lockdowns, unprecedented gold prices, and inauspicious periods based on religious beliefs.

As bullion imports improved during the July-September period on a quarter-on-quarter (QoQ) basis, a Motilal Oswal report has said that the improved demand shows revival in confidence among jewellers about the strong festive and wedding demand anticipated in the fourth quarter of 2020.

Citing the recent World Gold Council data, the Motilal Oswal report said that net bullion imports, which contribute 85-90 per cent of India’s gold supplies, saw a sharp recovery in third quarter of 2020 (3QCY20) after a deep plunge in the quarter before that. While gross imports and exports both plunged sharply in 2QCY20, the revival in exports was much lower than that in imports in 3QCY20.

Accordingly, while net bullion imports had fallen 96.4 per cent YoY to just 9 tonne in 2QCY20 amid stringent lockdowns, the volumes saw a sharp rebound to 90.5 tonne in 3QCY20, up 8.2 per cent. Although the growth is on a soft base of 3QCY19, it comes after four consecutive quarters of decline, it said.

“We believe this rebound is indicative of jeweller confidence in the strong festive and wedding demand anticipated in 4QCY20. Titan indicated in its post results call last week that the first 10 days of the festive season has been in positive territory,” the report said.

As per the World Gold Council’s latest data jewellery demand was severely affected during July-September with volumes down 48 per cent YoY to 52.8 tonne in 3QCY20. The demand was impacted by recurring lockdowns, unprecedented gold prices, and inauspicious periods based on religious beliefs, the report said.

“Nevertheless, there was a modest sequential recovery of 20 per cent QoQ in the gold jewellery demand,” it said.

New Ways Gemologists Are Identifying Lab-Grown Diamonds

Experienced diamond cutters and gemologists are improving their ability to identify certain lab-grown diamonds with loupes and microscopes. How have they been able to do this without advanced laboratory equipment? By learning to recognize distinctive inclusion types when they occur.

1. Metallic inclusions in HPHT-grown crystals

The HPHT process replicates the natural conditions under which diamonds formed below the earth’s surface from subduction. A carbon source, a diamond seed, and a metallic catalyst are put into a cell. That cell is placed into a massive mechanical press, where the contents are heated to near 1,400 C and subjected to staggering pressure. Upon reaching a certain temperature, the metallic catalyst begins to melt, dissolving the carbon, and the enormous pressure causes precipitation to the diamond seed, growing a larger diamond.

The use of that metallic catalyst permits growth to occur at lower temperatures, but a frequent result of the HPHT growth process is metallic remnants, which remain trapped inside the crystal. These remnants often have a man-made appearance when seen under magnification, and they are frequently reflective—unlike any naturally occurring inclusion type.

2. Planar inclusions in CVD-grown crystals

The CVD process does not grow crystals in the same way that natural diamonds grow. Instead, hydrocarbon gas is superheated in a vacuum chamber to between 800 and 1,000 C. At that point, carbon atoms begin to separate from their molecular bonds. The released atoms descend and land on a flat wafer of previously grown HPHT synthetic diamond substrate, growing the crystal vertically in parallel layers. Depending on equipment quality, cleanliness, and production goals, crystal growth can undergo a series of stops and starts during the process.

A byproduct of vertical growth is the possibility of characteristics that become grouped together on a single linear plane within the finished crystal. Such structured planar inclusion groups rarely or never occur in natural gemstones.

3. Quality control

Over the past several years, the rising visibility and popularity of lab-grown diamonds have created a “lab-grown diamond rush.” As more and more growers enter the arena, lab-grown rough output has taken on more variability. This variability can be exaggerated by entities entering the field with less capital resources, lower quality equipment, presses converted from industrial to gem-quality use, contamination confounders, etc. Turnaround choices also play a role. When a growth process is pushed to maximum speed it will increase the grower’s output, but it will also increase the likelihood of inclusion types that experienced gemologists can identify as distinctive to lab-grown diamonds.