CH17 Kimberlite (PHASE 4)

CH-17 Kimberlite

*Information in this current blog is based on information obtained up to mid 2018 and should be considered legacy at this time and should no longer be relied upon.*

CH-17 was originally discovered in the 2010 winter/spring program.
This kimberlite is under lake, so the initial drillhole was started in 2010 winter.
It only hit 3 metres of kimberlite before the program wrapped up.
This confirmed kimberlite material, but was not enough to perform a caustic result on.

The subsequent winter, another hole of 195 metres was completed.
Also, it's twin anomaly (200 metres apart) was drilled in 2011 as well and is named CH-51

Excerpt: (May 20th, 2010)

"The discovery of CH-17, 35 kilometres north of the nearest known kimberlites, CH-6 and CH-10, is further confirmation that Chidliak is a highly prospective and large Canadian diamond district. Formerly geophysical anomaly 166, CH-17 is the northernmost of two high-priority magnetic anomalies, 165 and 166, that have similar geophysical characteristics and are situated 200 metres apart under the same lake. Each of the anomalies has estimated surface expressions of at least one hectare. With this discovery, Peregrine management is confident that anomaly 165 is likely also a kimberlite.

The CH-17 drill core was described in the field as being macrocrystic olivine-rich kimberlite, containing country rock and mantle xenoliths, and abundant kimberlite indicator minerals. Pyrope garnet and chrome diopside grains up to 30 and 15 mm in size, respectively, were observed.

The CH-17 kimberlite is the first target drilled this year and the seventeenth kimberlite discovered at Chidliak since 2008. The discovery was made by drilling a vertical core hole from lake-ice into the centre of the high-priority magnetic anomaly and kimberlite was intersected underneath 41 metres of water and 2.5 metres of overburden. Three metres of kimberlite drill core was recovered before the hole was terminated due to drilling difficulties. A map showing CH-17 and the adjacent anomaly 165, and photographs of drill core, are available at: http://www.pdiam.com/assets/docs/pdf/chidliak613.pdf.

A second hole was not immediately attempted at CH-17 to allow for a thorough review and analysis of the drilling issues by Peregrine and the drilling contractor. While awaiting delivery of drill supplies, a geophysical anomaly 1.6 kilometres north of CH-17 was drilled because of its proximity to a favourable kimberlitic indicator mineral train. No kimberlite was intersected and the anomaly was explained by magnetic gabbro. The indicator mineral train is now interpreted as having likely originated from CH-17 and anomaly 165.

Since the CH-17 discovery hole was terminated on May 3, there have been ten days where weather did not allow access to the drill because of low visibility and/or high winds and blowing snow. In addition, unseasonably warm local weather has led to the formation of slush on the lake hosting CH-17 and anomaly 165. Both CH-17 and anomaly 165 cannot be efficiently drilled from the lake shore. For safety reasons, after a comprehensive analysis by an independent ice engineer, Peregrine has decided to postpone further drilling on the lake-ice at this particular locality until the spring of 2011. The drill is currently being moved to test two additional lake-based targets, anomalies 290 and 291 (see map at link noted above), that have more favourable lake-ice drilling conditions, and drilling is likely to commence in the next few days. Up to 30 land-based kimberlite targets are expected to be drilled this year during the spring and summer programmes at Chidliak."

Caustics: (Sept. 12th, 2011)

"As announced on April 20, 2011, CH-51 was discovered by drilling one vertical core hole and is located under a lake. A 228 kilogram sample of drill core yielded 76 diamonds larger than the 0.106 mm sieve size including three commercial-size (+0.85 mm) stones weighing a total of 0.04 carats (Table 2). The CH-17 kimberlite was discovered in May 2010 and is located 200 metres north of CH-51 under the same lake. Insufficient drill core was recovered in 2010 from this kimberlite to process for diamonds. As announced on June 2, 2011, a vertical hole was drilled into CH-17 this year and a 143 kilogram sample yielded 41 diamonds larger than the 0.106 mm sieve size, including two commercial-size (+0.85 mm) stones (Table 2)."

In a 142.7 kg sample, a total of 41 stones were found and spread out amongst several sieves heading into the commercial area.

The 1.18 mm sieve had 1 stone drop on it, giving an implied grade of 35 cpht.

CH-51 had similar population over several sieves.

Both CH-17 and CH-51 will get a good look at in the future.

The lake problem is an issue that keeps both of these as low priorities, yet there is potential that these both make it into an extended mine plane.

This is falling into the Phase 4 category.





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