One thing that just popped into my mind was that at Stornoway's booth at PDAC I reviewed a particular picture of AV1 discovery, with the pipe (?) dimensions (225 metres by 50 metres) overlaid on a picture of the lake. I was surprised by the very small size of that occurance. I guess I had something more significant immagined. SInce I'm on the topic, here is a wire Will on SWY:
Stornoway seeks new Aviat kimberlites
Stornoway Diamond Corp (TSX:SWY)
Shares Issued 72,634,195
Last Close 3/21/2005 $1.74
Tuesday March 22 2005 - Street Wire
by Will Purcell
Eira Thomas's Stornoway Diamond Corp. has busy plans for its Aviat diamond project on Melville Peninsula this year. The company began poking around the area several years ago and produced some promotable diamond counts from a kimberlite outcrop early in 2003. Since then, Stornoway and its partners turned up several more kimberlites nearby and identified a massive corridor of indicator minerals running across the central part of the property. As a result, Stornoway has a wealth of geophysical targets to test within that area and the partners could drill as many as 50 holes in the coming months. Based on the earlier results, the chances seem good that Aviat will produce some new diamondiferous kimberlites.
The Aviat play
It was John Robins and Lawrence Barry's Hunter Exploration Group that started the Aviat play. The prospectors saw some promising geology and had enough luck with a regional indicator mineral sampling program that they picked up about 500,000 hectares of ground. Hunter wasted little time in optioning off big slices of its play, turning to two juniors in promoter Don McLeod's Northair group of companies.
One of the new partners was Northern Empire Minerals Ltd., which Mr. Robins was running, while the other was Stornoway Ventures Ltd. Each company had a 35-per-cent slice initially, but their first quick look at Aviat delivered enough promise that the two companies decided to merge in 2003, with Ms. Thomas as its president.
The deal required the two partners to spend $2-million by the fall of 2005 to earn their combined stakes, but Aviat soon fetched a higher price. In the spring of 2003, BHP Billiton Ltd. bought a 20-per-cent participating interest in Aviat from Hunter for $7.125-million in cash. That implied a value of more than $35-million for the project as a whole, which produced its first diamondiferous pipe just a few months before.
The Aviat play grew considerably in 2003. The partners picked up large blocks of ground as prospecting permits, and the project swelled to more than 2.8 million hectares early that year. Aviat began to shrink after that, as Stornoway and BHP quickly checked out the huge play. The project now contains about 1.8 million hectares of ground, although Stornoway and BHP also added interests in new blocks farther to the south through another series of deals.
The Tremblay corridor
The early indicator mineral promise eventually expanded into the Tremblay corridor, a swath about 75 kilometres long and up to eight kilometres wide that delivered encouraging arrays of mineral grains. The feature, which may contain many individual indicator mineral trains, became apparent after a busy 2003 till sampling program.
The partners picked through about 2,400 samples collected that year, and the better samples outlined several other potential areas of interest outside the Tremblay zone. Still, it was within the latter area that Stornoway and BHP concentrated their big push last summer, in an exploration season shortened by miserable weather.
Stornoway did not have to stray far from its first kimberlite discovery. The outcropping AV-1 kimberlite lies within the Tremblay corridor, as do several other recent finds in the immediate vicinity. Those diamondiferous bodies undoubtedly account for a healthy portion of the indicator promise within the zone.
Nevertheless, there is plenty of mineral promise in the areas lying up-ice from the AV kimberlites. Further, the till sampling produced elevated counts well down-ice from the diamondiferous bodies. The results suggest that the Tremblay corridor received new surges of indicators from other bedrock sources. That points to the likelihood that a cluster of kimberlite pipes extends in that direction as well.
The Tremblay corridor produced some promotable chemistry over recent years. Stornoway and BHP were quiet about their geochemical work at first, but the Aviat partners became chattier about their mineral grains after the most recent investigation. That effort saw nearly 4,200 more till samples collected across the Aviat play, including 2,700 from the Tremblay zone alone.
The mineral haul included an abundance of pyrope garnets. About 40 per cent of the haul met either the G-9A or the G-10A classification. That pointed to a source that sampled the diamond stability field. The result is no great shock, given the diamond counts from AV-1 and its sister kimberlites, but it could bode well for any new finds along the swath.
Perhaps the most promising aspect of the Tremblay corridor is a 20-kilometre stretch that contains kimberlite boulders strewn about on the surface. Stornoway thinks that the float material comes from kimberlite bodies that remain undiscovered. As a result, the big Aviat drill program should catch the market's notice in the coming months.
The AV encouragement
Interest in the Aviat play surged early in 2003, when Stornoway produced the first set of diamond counts from AV-1. The partners discovered the little outcrop from the air during the summer of 2002, but kept the find quiet for several months as they pursued their extra prospecting permits.
The unexpected news of diamonds sparked a market frenzy. A Stornoway share cost just a dozen pennies in the fall of 2002, but the stock topped the $1.70 mark when the company revealed its first set of AV-1 counts. Added promise from the Aviat play continued to sustain speculative interest and Stornoway's shares traded as high as $2.99 early in 2004, when new results supported the earlier hopes.
Stornoway and its partners eventually processed over 2,180 kilograms of kimberlite from AV-1, coming up with just over 3,000 diamonds. That suggests a rate of about 1,400 diamonds per tonne, and a favourable diamond size distribution curve accompanied that toutable tally. About one-quarter of the AV-1 diamonds were large enough to sit on a 0.30-millimetre screen and just over one-eighth of the parcel remained on a 0.425-millimetre sieve.
About 2.5 per cent of the diamonds clung to a 0.85-millimetre mesh, which is typically the cut-off used for a first small mini-bulk test. That outcome offered hope that AV-1 had an encouraging grade and two small samples lived up to their billing. In all, Stornoway processed just over 10 tonnes of AV-1 rock, recovering about 8.6 carats of diamonds.
That points to a grade of about 0.83 carat per tonne, which could be of economic interest, given an equally promising diamond value. Tonnage is still a concern at AV-1, although the body now seems much larger than first thought. The first outcrop was just 40 metres long and eight metres wide, but AV-1 grew to about 225 metres by 50 metres after a big drill effort. Still, the Aviat partners would undoubtedly have to add new finds to make a profitable mine on Melville Peninsula.
The Aviat partners do seem off to a good start in that hunt, with several other significantly diamondiferous discoveries near AV-1. The company's best diamond counts from 2004 came from kimberlite boulders on the surface of an area called AV-5. Just under 50 kilograms of the float produced 93 diamonds larger than a 0.106-millimetre sieve, or nearly 2,000 stones per tonne.
That was roughly 40 per cent above what AV-1 delivered, and AV-5 has a promising size distribution to back up the greater content. Over 25 per cent of the diamonds sat on a 0.30-millimetre screen and 13 per cent of the gems clung to a 0.425-millimetre mesh. There were three diamonds larger than a 0.85-millimetre screen in the material, or about 3.2 per cent of the haul. That was an encouraging sum, considering the tiny amount of rock in the test.
With a comparable diamond size distribution and higher stone tallies, AV-5 has the potential to be the best of the AV kimberlites. As a result, Stornoway and its partners will make finding a bedrock source for the AV-5 kimberlite a top priority for this year's drill program.
AV-4 also yielded promotable diamond counts last year. Stornoway processed about 540 kilograms of rock from the body, most of it from core drilled up during a four-hole program. The rock contained 565 diamonds, or just over 1,000 stones per tonne. That was about 30 per cent less than the company produced from AV-1. Nevertheless, there are hints that AV-4 has a slightly better size distribution curve. That could be a big equalizer.
About 28 per cent of the diamonds sat on a 0.30-millimetre sieve and 16 per cent of the stones remained on a 0.425-millimetre screen. There were 18 diamonds that clung to a 0.85-millimetre sieve, or about 3.2 per cent of the parcel, and one diamond was large enough to remain on a 1.7-millimetre cut-off. Because of the coarser distribution curve, both AV-1 and AV-4 produced 0.85-millimetre diamonds at roughly an equal rate. That could bode well for AV-4, if the early diamond counts are representative of the body.
Stornoway thinks that AV-4 could be comparable in size with AV-1, although the company does not yet have a good handle on the geometry of the kimberlite. One angled hole hit 47 metres of kimberlite, while a second delivered a 61-metre intersection. Two step-out holes managed lesser thicknesses. It will take added drilling to better determine the grade and tonnage potential at AV-4, and that work could be in the cards for later this year.
The land-based features will likely be tested this summer. Meanwhile, Stornoway and its Aviat partners will get their drills turning on several lake-based targets. Based on the diamond results from the three main AV kimberlite sites and a few lesser bodies, any kimberlite hit should prove promotable.
Stornoway lost nine cents on Monday, closing at $1.74 on 152,000 shares. |
