The area of the OX deposit is underlain by volcanic rock of the Lower Jurassic Telkwa Formation (Hazelton Group) and sedimentary rock of the Middle Jurassic Smithers Formation (Hazelton Group). A stock of the Late Cretaceoeous Bulkley Plutonic Suite intrudes the strata, consisting of a 400 by 600 metre granodiorite porphyry plug.
Potassic, albitic, propylitic, sericitic and argillic alteration are evident at the deposit and are defined by biotite, chlorite, sericite, epidote, albite, magnetite and hematite alteration.
The Ox porphyry copper-molybdenum deposit occurs in an area underlain by felsic tuff, andesitic tuff, sandstone and siltstone of the Lower-Middle Jurassic Hazelton Group. Intruding the sequence is a 400 by 600 metre Upper Cretaceous granodiorite porphyry plug.
The Ox deposit is roughly crescent shaped with some fault controlled offsets and is characterized by disseminated and vein controlled porphyry copper-molybdenum mineralization. Mineralization contains pyrite, chalcopyrite, and molybdenite hosted in hornfelsed sedimentary rocks near the western margin of a granodiorite porphyry stock (Ox intrusive).
The main host to mineralization is an intense stockwork of veins and fractures in the hornfels zone. In general, copper mineralization is most prominent in the hornfels while molybdenum is concentrated in porphyry dikes with small amounts in the hornfels. Nine vein types are developed in four stages that form part of the stockwork. The most common metallic minerals are pyrite, chalcopyrite, bornite, hematite, magnetite, pyrrhotite and molybdenite. Very minor late veins contain some sphalerite and galena.
A fine-grained feldspar porphyry occurs as dikes or sills within the mineralized zones and contains mineralization and alteration similar to the surrounding sedimentary rocks. A coarse crowded feldspar biotite porphyry forms an intrusive body on the east side of the Ox mineralized zone. The crowded porphyry does not contain significant zones of mineralization but does have sericite, chlorite, pyrite, and clay alteration with weak copper and molybdenum locally. Quartz veining is typically weak. Several drill holes indicate the crowded porphyry is locally in fault contact with the adjacent mineralized sedimentary rocks.
Brecciated zones and thin cataclasite zones are common as faulting plays a strong role in controlling and bounding mineralization at the deposit. Late episode, fault-controlled calcite and iron-carbonate-quartz and base metal sulphide veins locally cut the Ox mineralization. Ten metres of quartz-carbonate veining (4 metres true width) with faint crustiform banding was encountered in one drillhole. The vein contains significant silver, lead and zinc over 10 metres
Mineralization has a gradational boundary on the west side whereas a crowded feldspar biotite porphyry (orange) bounds mineralization on the east side. In general, mineralization appears to be highest grade at or near surface and adjacent to the intrusive contact, with an apparent grade decrease with depth, with the main mineralized body extending 150 to 250 metres below surface. Significant alteration is still present in the rocks underlying the mineralized zone but copper and molybdenum values are generally weak and patchy.
WORK HISTORY
Geological reserves are 17,234,900 tonnes grading 0.33 per cent copper and 0.035 per cent molybdenum (Vancouver Stock Exchange Offering of Rights July 17, 1985 - Consolidated Silver Standard Mining Ltd.).
The Ox porphyry copper deposit was discovered in 1968 during a prospecting program carried out by Silver Standard Mines Ltd. Between 1968 and 1981, work on the Ox lake property included geological mapping, IP, EM and magnetometer geophysical surveys, soil sampling, trenching and diamond drilling.
In 2007, Gold Reach Resources Ltd. acquired the 14 claims known as the Ox Lake property from Silver Standard Resources Ltd. and completed 26 diamond drillholes totaling 6142 metres and a 3D-IP geophysical survey over the property. Drillhole Ox07-05, the best of the program, intersected 127.5 metres grading 0.3031 per cent copper and 0.0311 per cent molybdenum, with a copper equivalency of 0.649 per cent (Assessment Report 29144).
In 2008, Gold Reach Resources reported an inferred mineral resource of 16,130,000 tonnes grading 0.3 per cent copper and 0.04 per cent molybdenum (Arseneau, G. (2008-03-20): Mineral Resource Estimate on the Ox Lake Mineral Property).
In 2012, Gold Reach Resources Ltd. completed an exploration program of diamond drilling, IP surveying, soil sampling and geological mapping. Highlights include drillhole Ox12-33, which intersected 304 grams per tonne silver, 11.9 per cent lead, 11.3 per cent zinc and 0.28 per cent copper over 4 metres (Press Release, Gold Reach Resources Ltd., November 12, 2012).
In 2013, Gold Reach Resources Ltd. conducted diamond drilling at the Ox Lake showing. Highlights include Ox13-59, which returned 53.2 metres grading 0.37 per cent copper, 0.063 per cent molybdenum and 1.39 grams per tonne silver (Press Release, Gold Reach Resources Ltd., July 10, 2013). Gold Reach Resources Ltd. also released an NI-43-101 compliant updated resource estimate for the Ox deposit which showed inferred resources of 52,650,000 grading 0.21 per cent copper, 0.03 gram per tonne gold, 0.022 per cent molybdenum and 1.25 grams per tonne silver, calculated using a 0.2 per cent copper equivalent cut-off grade (Press Release, Gold Reach Resources Ltd., February 11, 2013).
In 2014, an unconstrained measured and indicated resource of 39,530,000 tonnes grading 0.04 gram per tonne gold, 1.53 grams per tonne silver, 0.20 per cent copper and 0.026 per cent molybdenum with an unconstrained inferred resource of 16,360,000 tonnes grading 0.03 gram per tonne gold, 1.36 grams per tonne silver, 0.17 per cent copper and 0.020 per cent molybdenum using a 0.20 per cent copper equivalent cut-off was reported (Boyce, R.A., Giroux, G. (2014-01-27): A Mineral Resource Estimate Update for the Seel and Ox Deposits -- Ootsa Property).
In 2016, an updated mineral resource for the Ox occurrence was reported at 33,696,000 tonnes measured and indicated grading 0.26 per cent copper, 0.04 gram per tonne gold, 0.027 per cent molybdenum and 1.5 grams per tonne silver, using a C$8.50/t NSR cut-off (Puritch, E. (2016-03-23): Updated Resource Estimate and Preliminary Economic Assessment on the Ootsa Property).
Refer to Seel for further details of the Seel property that was held by Gold Reach Resource from 2003 to date (2015).