43-101 2007 Technical Report On The San Antonio Project, Baja ...
43-101 2007 Technical Report On The San Antonio Project, Baja ...
43-101 2007 Technical Report On The San Antonio Project, Baja ...
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Derry, Michener, Booth & Wahl Consultants Ltd. Page 3713.0 SAMPLE PREPARATION, ANALYSES and SECURITY13.1 Reverse Circulation SamplesAll logging of samples is made in-site by qualified Geologists at the same time that the samplesare being collected by the local (<strong>San</strong> <strong>Antonio</strong>) trained drill helpers.All samples are taken by Pitalla staff in a pickup truck at the end of the shift to the centrallogging facility at <strong>San</strong> <strong>Antonio</strong> (about 10 minutes drive) where they are stored under lock andkey in a gated and fenced compound (finca) with security guards watching the premises 24 hoursper day. <strong>The</strong> core shack and yard in <strong>San</strong> <strong>Antonio</strong> village is rented from the family of one of thestaff who acts as a daytime security guard.<strong>The</strong> samples are packaged in rice sacks and trucked to the city of La Paz by bonded carrier andthen by truck ferry (8 hours) to the Mexican mainland in Sinaloa State. <strong>The</strong> truck then proceedsto Hermosillo, Sonora (8 hours) and to the ALS Chemex preparation facility. <strong>On</strong>ce prepared, thepulps are forwarded by ALS to the ALS Chemex labs in North Vancouver, Canada where Aucontent is measured by fire assay with Atomic Absorption finish as well as by aqua regiadigestion and ICP analysis to quantify trace elements. When needed, over- range Au analysis(>10 ppm) is made by fire assay and Gravimetric finish.13.2 Rig DuplicatesIn addition, every 30 samples, a rig duplicate sample is obtained from the vertical discharge(50%), then is split and stored as individual samples in the warehouse; the other 50% is split asnormal in two 25% samples, which are packed in individual pre-numbered bags to be sent to thelab as duplicate samples.13.3 Drill Core samplesAll sampling is carried out at 1.52 m (5 feet) intervals. Core barrels are 10 feet long. In a fewareas of poor recovery, samples are combined into lengths greater than 1.52 m. <strong>The</strong> 1.52 msample intervals are not tied to lithology, alteration or structure. Most of the sulphide core isfairly hard and competent and a diamond saw is used to cut the core in half (lengthwise). Faultzones (clay gouge) and other alteration, or small rubble zones are split with a spoon. Oxide coreis normally solid clay and is cut in half (lengthwise) using a butcher knife; solid lumps are splitwith the hammer splitter. Care is taken to keep the saws as clean as possible. <strong>On</strong>e half of the coreis put into individual sample bags while the other remaining half is retained in the core boxes andstored on site in <strong>San</strong> <strong>Antonio</strong>. <strong>The</strong> plasticized cardboard core boxes, standard in Mexico, canstore four runs of 1.52 m.Core is washed initially to remove drilling fluids, and then logged and photographed andrecovery noted by measuring the net amount received between drillers wooden markers, whichare marked in feet and meters.