PRB New Drill Results - Initial Comments
posted on
Jun 06, 2012 12:59PM
I have looked at the results overnight to try to understand the general trend, but haven't got time yet to go over the details with my shoe box model. Actually it should be a 2-shoebox-model, one big (2100 m long) which cover the "the red zone" on the air survey map (PRB website) and a smaller/shorter approximateley half the length covering the blue and green zone) just on the north side of the of the big box. The two are joined at the hip just like Siamese twins.
- Depth extension drilling (1st table of NR): The holes in this blue green portion (survey map) indicates a 203m (depth) extension of the mineralized zone, as indicated by the NR. However this was also step-out drilling (to the north) for the smaller shoebox by approximately 200m? One can attempt a rough calculation using the shoebox model taking into account the increased depth and step-out (width of box) to have a first order estimate of the size of deposit. However, this would require some other details such as drill angle, etc. (But, initial guess: Increase in inferred portion in the next resource update)
- Shallow infill drilling (2nd table): As indicated in the NR, these infill drill results confirm the continuity of the mineralized zone defined by previous results (Guess: next updated resource estimate would show a higher indicated value)
- Deep Infill drilling (3rd table): Hole 194, left side of survey map, showing better grade (1g/t) at depth (encouraging). But the rest @ 0.5 g/t would be considered economical for a lower grade high tonnage mines (some producers are making money at 0.24% g/t)
- Waste modelling down-dip (4th table): Hole 162, left side of survey map south of 194. Not results @0.5g/t over almost the entire length of the hole with 13m @ 1.0g/t at depth (again encouraging). Don't quite understand why it was called "waste modelling". Any geo in the house?
If the above guesses and observation are correct, then Borden would be within reach of the a 10 oz Au target. The resource estimate should include one with a cut off grade of 0.3g/t. Also, the total Indicated + Inferred should be considered to compared with TRR estimate, noting that most of the TRR resource is in the inferred catergory, using 0.3 g/t cut off grade (0.9M + 5.94M Infer = 6.84M oz Au, i.e. 87% Infer)... and IAM paid $565 M for it.
It would be fine for the NR to refer to the resource estimate for the high grade zones, but again, for comparison purpose with TRR PRB should flaunt the values using the I = 4.05 M oz/Au and Infer: 1.8 M oz Au, hence I + Infer = 5.85 M. Although the total resource and overall grade are slightly lower than that of TRR, PRB has quite a bit of silver to add. We should not forget that most of the PRB resource is in the Indicated catergory (70%) compared to 13% for TRR, hence TRR value of 6.84M oz has a larger uncertainty band. With the new drill results it's a sure bet that PRB next update would be between TRR 6.84 M and 10 M oz Au, and probably closer to 10M oz @ 0.30 g/t cut- off grade.
With a better outlook for PoG, PRB should fetch at least $600M ($600M/65M = $9.23/s) for Borden alone. So, we wait for better time.
Sounds reasonable?
goldhunter