Encouraging diamonds in Q1-4 bulk sample

North Arrow Minerals Inc. July 28 announced that the final recoveries from an 1,823.6-dry-metric-ton bulk sample collected last year from the Q1-4 diamond deposit indicate the potential for a population of high-value, fancy orange and yellow diamonds in the kimberlite on the Naujaat Diamond project in Nunavut.

The results, representing the final 30% (498 dmt) of the bulk sample, is entirely from the A88 unit of the Q1-4 deposit and follows results from the initial 70% of the sample reported in April.

You can read about the first 70% at North Arrow reports fancy Q1-4 diamonds in the April 29, 2022, edition of North of 60 Mining News.

“The 2021 bulk sample has confirmed the presence of an important, potentially high value population of fancy orange and yellow diamonds in both the A28 and A88 units of the Q1-4 diamond deposit,” said North Arrow President and CEO Ken Armstrong. “This is highly encouraging, as is the recovery of a seven carat diamond – the largest stone recovered to date from the Q1-4 deposit and, although it classifies as boart – an indication of the potential of Q1-4 to produce larger diamonds.”

This large sampling program was funded by Burgundy Diamond Mines, an Australia-based company that entered into a deal with North Arrow to earn a 40% interest in the Naujaat project by investing C$5.6 million to collect a 1,500- to 2,000-metric ton preliminary bulk sample from the Q1-4 diamond deposit at Naujaat.

Q1-4 kimberlite is the largest and richest of at least eight kimberlite pipes North Arrow has identified so far at the project.

According to a calculation completed in 2013, the top 205 meters of the Q1-4 kimberlite hosts 48.8 million metric tons of inferred resource averaging 53.6 carats per hundred metric ton, or 26.1 million carats of diamonds.

“The completion of sample processing and diamond recovery from the 2021 bulk sample has further confirmed the presence of a potentially high value, fancy orange and yellow diamond population in the Q1-4 kimberlite,” said Managing Director and CEO of Burgundy Diamond Mines Peter Ravenscroft.

The reported diamond results are categorized with a bottom sieve size of +9 DTC (Diamond Trading Company), which is currently the smallest sieve size for which diamonds are detected and fully recovered using X-ray transmission (XRT) optical sorting technology.

Highlights from the final 30% sample include:

• The A88 bulk sample recovered 99 diamonds of greater than +9 DTC weighing 55.8 carats from 498 dmt.

• Seven, 2.17, and 2.02 carats are the three largest that were recovered, with the seven-carat stone being the largest diamond recovered to date from the Q1-4 diamond deposit.

• 10.1% fancy color diamonds – 10 of the 99 diamonds classify as fancy color diamonds (12.8% by carat weight).

North Arrow Minerals Inc.

The Q1-4 kimberlite is located in southern Nunavut, about 5.6 miles (9 kilometers) from the hamlet of Naujaat on the shore of Hudson Bay.

• Three of the fancy diamonds classified as either “intense” or “vivid” – the two highest color saturation classes and an important indicator of the potential value in fancy color diamonds.

• Nine of the fancy diamonds classify orange as the primary color, with orange being considered amongst the rarest of colors for natural diamonds.

• +9 DTC sample grade of 11.2 carats per hundred metric tons, compares favorably with a smaller sample collected from the same geological unit in 2017.

“Next steps in our ongoing evaluation will include modelling of the size distributions of the fancy diamonds, as well as consideration of options for test cutting and polishing the fancy colour diamonds to better understand the colour characteristics of the final, polished diamonds, and their potential for enhanced value in the creation of luxury jewelry,” said Armstrong.