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Harte Gold’s Sugar Zone: A Lesson in Creative Grade Reporting

Harte is likely reporting on all intervals that showed gold values in the assays and excluded those intervals that were completely barren. But do these low grade intervals add value to the project? You decide.

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TORONTO, ONTARIO–(Marketwired – Oct. 29, 2013) – HARTE GOLD CORP. (“Harte Gold”) (TSX:HRT)(FRANKFURT:H4O) is pleased to announce assay results from an additional seven holes focused on the Jewelry Box Zone (“JBZ”) located at the north end of the Sugar Zone Deposit. The assay results in the table below confirmed our expectations that the JBZ grades and widths are higher than the average for the Sugar Zone Deposit.

Harte Gold’s Sugar Zone Deposit is a low to moderate grade gold deposit located in NW Ontario, Canada. The deposit is typical of gold deposits in this region: structurally controlled mineralization within an Archean-aged (2.5+ billion years) greenstone belt.
Hole # Zone From To Grade (g/t) Width (m) Visible Gold
SZ-13-53 Lower Zone 54.94 57.40 13.74 2.46 VG
including 54.94 56.40 21.30 1.46
SZ-13-55 Upper Zone 17.90 18.85 10.58 0.95 VG
Lower Zone 52.60 56.60 5.60 4.00 VG
Including 52.60 54.00 13.69 1.40
SZ-13-56 Upper Zone 14.00 19.70 3.67 5.70 VG
including 18.47 19.70 8.94 1.23
Lower Zone 56.00 57.90 2.77 1.90
SZ-13-57 Upper Zone 12.00 16.00 4.74 4.00
including 15.00 16.00 6.84 1.00
Lower Zone 45.40 46.70 5.68 1.30 VG
SZ-13-58 Lower Zone 96.60 101.79 27.40 5.19 VG
including 96.60 97.85 109.08 1.25
SZ-13-59 Lower Zone 106.30 108.80 11.41 2.50 VG
Including 106.30 107.50 21.20 1.20
  • Drill intercepts represent core intersection lengths and true widths may vary
  • SZ-13-54 was drilled outside the JBZ, assay results contained no significant values
There are many ways to interpret drill results. We will often ignore the highlights or “including” intervals since they can distract from the big picture and aren’t always helpful: After all, in a mine environment the full width of a zone will be mined. However, that method assumes that the reporting company has reported full intervals within a reasonable cut off grade and not tried to overstate the size or grade of their mineralized zone. Let’s use this short list of drill results to do some example calculations:

In Drill Hole SZ-13-58: Harte Reports 27.4 g/t gold over 5.19 meters including 109.8 g/t over 1.25 meters. These are very good grades, but the problem is that the narrow high grade interval is skewing our average. Let’s remove it from larger interval to see what’s left.

First we multiply our intervals by our grades:

5.19 m x 27.40  g/t = 142.206 (larger interval) 
1.25 m x 109.08 g/t = 136.35  (including)

Then we take the difference between the two:

142.206 - 136.35 = 5.856

Calculate the remaining interval length:

5.19-1.25 = 3.94 m

And divide our meter-grade difference by the remaining drill interval:

5.856 / 3.94 m = 1.486 g/t

What we get is almost 4 meters grading at less than 1.5 g/t! Compare that to the reported average of 27.4 g/t for the full 5.19 m interval.

1.5 g/t is not especially good and below the cut-off grade of 3.0 g/t that Harte used in their Preliminary Economic Assessment. If you run the same calculations for all the intervals above you’ll find that only one (13-57 upper) grades above 3 g/t for the entire length. Harte is likely reporting on all intervals that showed gold values in the assays and excluded those intervals that were completely barren. There is nothing overtly untoward here and this type of highlighting is common practise, but do these low grade intervals add value to the project? You decide.

The JBZ drill program has been successful in both confirming and expanding the extent of high grade – near surface mineralization. Harte Gold is currently preparing a resource calculation for the JBZ to establish its potential for bulk sample mining. Five holes drilled to the south of the JBZ will not be followed up at this time.

Stephen G. Roman, President and CEO stated, “We are pleased with the continued high grade assay results from the Jewelry Box Zone. The high grade assays and wider mineralized widths combined with the JBZ’s proximity to surface may provide quicker and less expensive access to the deposit under the Advanced Exploration and Bulk Sample Program.”

Road Construction

Construction of the mine site access road is progressing well with completion now targeted for mid November. The road will connect the Sugar Zone Deposit to Highway 631 which in turn provides direct access to the Trans Canada highway. Construction of the road is a key milestone in the development of the Sugar Zone property as it significantly

reduces travel time to and from the property and will facilitate regional exploration programs across the property. Please go to www.hartegold.com for recent pictures

QA / QC Statement

Diamond drill holes were drilled with HQ sized core in order to obtain larger sample volumes of the mineralized zones. The core was sealed and delivered by the drilling contractor to Harte Gold’s facilities located in White River, Ontario. The mineralized sections of the cores were photographed for reference, logged and mineralized sections were sawn in half. Sample lengths were 0.5 meters. Half core samples were bagged, sealed and delivered to Activation Laboratories in Thunder Bay, Ontario, an accredited laboratory. The remaining core is stored on site for reference. Samples were assayed by the fire assay method using an atomic absorption finish on a 50 gram pulp split. A quality assurance and quality control program (QA/QC) was implemented by Harte Gold and the laboratory to ensure the precision and reproducibility of the analytical method and results. The QA/QC program includes the insertion of standards, blanks and field duplicates in the sample batches sent to the laboratory and a systematic re- assaying of samples returning values above 3 g/t Au by the fire assay method using a gravimetric finish. Drill programs are conducted under the supervision of George A. Flach, P. Geo, Vice – President of Exploration for Harte. Mr. Flach is the Qualified Person (QP) as defined in National Instrument 43-101.

This is a fairly straightforward, but important QA/QC statement. Read more about QA/QC here. HQ core is 2.5 inches wide and is a commonly used core size in mineral exploration. Anything smaller shouldn’t really be used unless there is a technical reason prevent the use of HQ.

About Harte Gold Corp.

Harte Gold Corp. is focused on the development of its 100% owned Sugar Zone property where it is permitting an Advanced Exploration project to test the Sugar Zone Deposit. The Sugar Zone property is located 60 kilometres east of the Hemlo Gold Camp and contains an NI 43-101 compliant Indicated Resource of 980,900 tonnes, grading 10.13 g/t for 319,280 ounces of contained gold (uncapped) and an Inferred Resource of 580,500 tonnes, grading 8.36 g/t Au for 155,960 ounces of contained gold (uncapped). Harte also holds the Stoughton-Abitibi property located on and adjacent to the Destor-Porcupine Fault Zone in the Timmins, Ontario Porcupine gold camp.

Common Shares Outstanding: 205,482,554

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