Celestine Mercer

I am a Research Geologist at the U.S. Geological Survey in Denver, CO. My areas of expertise include igneous petrology, economic geology, experimental petrology, geochemistry, and volcanology. I spearhead the melt inclusion analysis capabilities in the Denver Inclusion Analysis Laboratory.


I'm interested in applying melt inclusion studies and experimental petrology to learn more about how metals are concentrated and partition from magmas into ore-forming fluids that generate economic ore deposits.

I am currently investigating: (1) magmatic contributions to iron oxide-rare earth element (IOA-RE) and iron oxide-copper-gold (IOCG) deposit genesis in the Missouri iron province, (2) concentrations and partitioning of Li in highly evolved rhyolites in the western US as a source for economic Li brines and clays, (3) quantifying critical elements (Li, W, REE) in rift related volcanic systems, and (4) testing the magmatic model for Carlin-type Au deposit genesis in Nevada. I recently completed a 5-year project entitled "Magmas to Metals" focused on melt inclusion and high-spatial resolution mineral geochemical analyses to explore igneous systems related to IOA-REE and IOCG mineralization in the St. Francois Mountains of SE Missouri.

Before coming to the USGS, I was a Postdoctoral Fellow at the Lunar and Planetary Institute in Houston, TX, where I studied the petrogenesis of the Moon by examining lunar returned samples including a newly found lunar meteorite. I was a Visiting Professor at Colorado College from 2009-2010 where I taught Introductory Geology, Planetary Geology, Petrology, and "Bubbling Magmas, Hot Springs, and Colorado's Premier Ore Deposits". During my Ph.D. I used petrologic and geochemical methods to investigate the magmatic-hydrothermal transition at the porphyry-Cu-Mo deposit in Butte, Montana, and the crustal "plumbing system" of a stratovolcano in the Cascades.


Ph.D., Geological Sciences, University of Oregon, 2009

B.A., Physics, Oberlin College, 2002

Recent Students

National Association of Geoscience Teachers-USGS Interns, 2018, 2014

St. Lawrence University Summer Internship Program, 2017

Denver Mayor's Program Intern, 2014

Lunar & Planetary Institute Intern, 2011

Denver Inclusion Analysis Laboratory

  • Bruker Hyperion 3000 FTIR microscope interfaced with Vertex 70 FTIR spectrometer. For quantification and mapping of dissolved H and C species in volcanic glass or minerals.
  • Melt inclusion preparation equipment. Leica binocular microscope, Nikon petrographic microscope, hot plates, grinding and polishing equipment.
  • Rapid-quench cold-seal apparatii with computer-controlled pressure and temperature cycling. These devices are currently in development and will be well equipped for experimental studies of upper-crustal magmatic-hydrothermal processes up to ~2 kbar (200 MPa; equivalent to ~6 km depth in the Earth) and ~850°C.
  • Ancillary experimental equipment. The lab also contains all necessary sample preparation and support equipment including a microwelder, microbalance, drying furnaces, etc.