The Kamitsue Project
- The Kamitsue property is located 10 km southeast of the Taio mine in the Northern Kyushu Epithermal Province.. The Taio mine, northern Kyushu’s largest gold mine, produced approximately 1.2 million ounces of gold at an average grade of 6.3 g/t between 1903-73 (1Garwin, 2005, 2Shikazono, 1986). Kyushu hosts two other plus million ounce gold producers, the currently producing Hishikari mine with 8.5 million ounces of gold at a grade of 47.3 g/t (Sumitomo Metal Mining Co. Ltd. website) and the Kushikino mine which produced 1.8 million ounces of gold at a grade of 6.7 g/t between 1914-74 (1Garwin, 2005, 2Shikazono, 1986) in the southern part of the island.
- At least 40 mine portals and associated workings from the pre-WWII era are noted within the property (3Watanabe, 2005), however no gold production records have been sourced to date.
- Detailed surface exploration over the property by the Metal Mining Agency of Japan (MMAJ) in the early 1990’s identified two distinct east-west trending coincident alteration / geochemical anomalies of areal size 5.5 km by 1.5 km and 1.5 km by 0.5 km respectively. Both zones reported anomalous gold, silver, arsenic, mercury + antimony; typical geochemical signatures of low sulfidation epithermal mineralization. High sulfidation epithermal clay alteration assemblages reported in MMAJ work may represent an earlier hydrothermal event.
The Kamitsue Project comprises twelve (12) contiguous Prospecting Rights blocks (4,069 Ha) near the town of Kikuchi in northern Kuyshu. Kamitsue hosts a large (exposed) area of alteration and geochemical anomalism with a signature typical of low-sulfidation epithermal style systems. These were defined by the MMAJ during regional metallogenic and follow-up prospect-scale surveys in the 1990’s.
No known historical gold production records exist for the pre-WWII era Kamitsue mine workings however Wantanbe, 20053 notes the presence of at least 40 mine portals and associated workings.
Exploration was undertaken from 1990 to 1992 by MMAJ as part of a regional metallogenic study which included regional gravity surveys, surface sampling (semi-regional and prospect scale), culminating in scout diamond drilling. Chronologically this included:
1984: Sumitomo geological sampling of historical mining portals.
1990: Geological mapping, geochemical sampling (300 rock chip samples) and alteration mapping.
1991: Prospect-scale rock chip sampling (399 samples) collected. This and previous work identified two distinct coincident clay-alteration / geochemical anomalies including a 5.5km by 1.5km east-west trending zone with anomalous gold, silver, arsenic, antimony and mercury and a smaller 1.5km by 0.5km zone with anomalous gold, silver, arsenic and mercury. A single inclined drillhole (3MAKC-5, 400m depth) targeted a Au-Ag-As rock geochemical anomaly and intersected a 1.6 m wide quartz vein zone which assayed 0.12 g/t Au & 11.1 g/t Ag from 341.9m (4METI, 1991).
Geology and Mineralisation
The majority of the property is underlain by Neogene andesite intrusions with volcanic equivalents including lavas, tuffs. Dacitic equivalents are found in the upper part of the sequence. Unconsolidated quaternary volcanic tuff deposits occur as a thin veneer occupying topographical highs.
Epithermal vein mineralization is hosted by an argillic alteration assemblage of illite-sericite-carbonate-pyrite-marcasite with strong E-W structural control. High sulphidation epithermal alteration assemblages are reported by MMAJ and may represent an earlier hydrothermal event.
MMAJ and Sumitomo describe epithermal mineralization as a series of sub vertical quartz-carbonate-pyrite+marcasite veins and veinlets, with crystalline, banded & drusy textures along with minor amounts of disseminated base metal sulphides (sphalerite/galena/ chalcopyrite).
Sampling by 5Sumitomo (1982) of historical mining portals reported values of <0.01-6.0 g/t Au and <0.5-6.0 g/t Ag, whilst MMAJ sampling in 1991-92 returned values of 0.001-0.33 ppm Au, 0.1-1.96 ppm Ag, 1-63 ppm As, 1-33 ppm Sb, 0.05-1.76 ppm Hg & 1-262 ppm Mo.
The Kamitsue project is located 10 km along strike from the Taio mine which produced approximately 1.2 million ounces of gold at a grade of 6.3 g/t. Historical gold workings on the property, together with a large scale coincident alteration and geochemical anomalism foot-print indicate potential near surface epithermal gold-silver vein targets.
The company believes this area is worthy of more detailed exploration and will seek to define the limits of the alteration around these vein systems by building on the existing data with detailed surface mapping, geochemical-sampling and geophysics to target new zones and extensions to known veins for scout drill testing.
1 Garwin et al. 2005. Tectonic setting, Geology, and gold and copper mineralization in the Cenozoic magmatic arcs of Southeast Asia and the West Pacific. Economic Geology 100th Anniversary Vol. pp 891-930
2 Shikazono, N. 1986, Ag/Au Total Production Ratio and Au-Ag Minerals from Vein-Type and Disseminated-Type Deposits in Japan, Mining Geology, 36(6), p 411 – 424.
3 Watanabe, 2005. Late Cenozoic evolution of epithermal gold metallogenic provinces in Kyushu, Japan. Mineralium Deposita (2005) 40: pp 307-323
4 METI, 1991-1997. Reports completed by MITI on the Takamine area (Years 3 to 9). The Agency of Natural Resources and Energy of MIT.
5 METI (1984- 1989): Report on the regional survey of the Hokusatsu-Kushikino region, Showa 58 (FY) to 63(FY). Ministry of International Trade and Industry.