Field Trip: Henderson Molybdenum Mine

Bob Golden or 303-569-3221
Jim Cappa or 303-866-3293

Fee: By March 1, 2006. $100 Member, $185 Nonmember, $50 Student

The Henderson porphyry molybdenum deposit is associated with a series of high-silica, alkali-rich highly differentiated rhyolite and granite porphyry intrusions.  Multiple ore shells were produced by the sequential emplacement of separate intrusions.  The Henderson mine is a panel caving operation that is currently expected to produce approximately 28,000 tons of ore per day in 2006.

It has been in production since 1976.  Since that time, large portions of the deposit have been mined out, and most workings have been covered with shotcrete to support the ground.  Due to the resulting limited extent of geologic exposures, the underground tour will emphasize the operational aspects and facilities of the mine.  The deposit geology, geologic model, and current exploration programs will be reviewed in the office, and via core samples and hand samples.  At least one development heading will be visited underground to view the geology of the deposit.

The field trip will depart from Keystone at 7am to arrive at the mine at 8 am and return in the late afternoon.  A field trip guidebook and lunch at the mine will be provided.