The Jinfeng gold deposit: mining the new frontier of China

Jinfeng is the largest known Carlin-type gold deposit in the Peoples Republic of
China, with a resource of at least 3.5 M oz gold. It is currently being developed by
Sino Gold Ltd., in conjunction with local partners. Development began in late 2004,
and full production is scheduled for mid-2006. Open-pit and underground operations
will produce approximately 180,000 ounces annually from refractory ore.
First operated circa 1850’s as a mercury and arsenic mine for Chinese medicines,
Jinfeng was rediscovered in the early 1980’s by the provincial Bureau of Geology and
Mineral Resources following a stream geochemical anomaly. They subsequently drilled
approximately 30 km of diamond core and drove 8 km of underground heading to
delineate a deposit of roughly 1.5 M oz. gold, but beneficiation of the sulfide-bearing
ore proved problematic. Sino Gold began an exploration program in 2002 that
included 45 km of diamond drilling and more than doubled the previous resource.
Jinfeng, previously known as Lannigou, is situated in SW Guizhou Province, an
agrarian area of steep hills and narrow valleys with elevations between 400 and
800 m. Rifting of the Yangtze craton during the Precambrian to Cambrian produced
the Dian-Qian-Gui sedimentary basin which now hosts numerous Carlin-type gold
deposits. Triassic turbidites host the vast majority of gold ore. The Triassic rocks
overlie Carboniferous through Early Triassic limestones which core the N-S elongate
Laizhishan dome less than 1 km to the west. The sequence has a multi-phase
deformational history dominated by NE-SW compression with evidence for lesser
amounts of NW-SE compression as well. These events have produced a complex
series of gentle to tight folds and thrust and transfer faults, and provided the setting
for gold mineralization.