The Mineral Sciences collections include minerals, rocks, meteorites, gems, and related synthetic materials. In overall significance the mineral collection probably ranks fourth in the United States and it is the most important west of Washington, D.C. The gem collection ranks third in the country after those at the National Museum of Natural History and the American Museum of Natural History. The mineral collection is world-wide in scope and boasts particular strengths in minerals from California, native gold, and gem crystals. The collections are being actively augmented principally through purchases and donations.
There are approximately 150,000 specimens, including more than 140,000 minerals, nearly 100,000 of which are micromounts, 3,000 rocks, 3,000 gems, and 50 meteorites. Approximately half of all known mineral species are represented in the collections.
In the early years, the collection grew primarily through the donation of numerous small collections. The most important of these was from the Los Angeles Chamber of Mines and Oils (1921) and included many fine specimens from Bisbee, Arizona. A stronger commitment to building the mineral sciences collection began in the 1970s resulting in a rapid growth of the collection through donations and purchases. The most significant mineral collections received in recent years have been those of Mark and Jean Bandy (1977-1980), Ben Chromy (1985), George Tunell (1989 and 1994), Jessie Hardman (2000), Julius Weber and Louis Perloff (2005), and Ben Frankenberg (2006). In recent years, numerous donations of high-quality display specimens by Mr. and Mrs. Hyman Savinar and Mr. Melvin S. Hindin have greatly enhanced the collection. The gem collection was initiated through a series of gifts between 1953 and 1961 from a Los Angeles jeweler, William E. Phillips. Major collections from Col. Frederick C. Hixon (1971-1977) and John Jago Trelawney (1988) elevated the Museum's gem collection to world-class stature.
The collection supports research in a variety of areas in materials science, climate science, pharmaceuticals, environmental remediation, petroleum science, ore deposits, exobiology, bio-mineralogy, and general mineralogical research.
Our research laboratory has been on public display since 2017. All experimental stations, collections, and equipment are on view and scientific content is communicated to the visitor by signage, gallery interpreter engagement, video, and social media to our more than 800,000 visitors a year.
The lab includes the following analytical equipment:
- Raman Microscopy: The Mineral Sciences Department is outfitted with a Horiba ExploRa+ dispersive Raman microscope. Two lasers can be selected, a 532 nm and a 785 nm, with automated calibration for each laser. Typical Raman spectra for the 532 nm laser can be collected from 70 cm-1 to 4500 cm-1, while the 785 nm laser spectral range is nominally from 40 cm-1 through 2500 cm-1. Slits can be used to obtain better spectral resolution from a selection of 50, 100, 200um, and the microscopic can be used in confocal mode by selecting a pinhole, 100, 200, and 500 um. Laser power at the sample is adjustable, with a maximum of 15.2 mW at the sample. Diffraction grating options are 600 gr/mm, 1200 gr/mm, 1800 gr/mm, and 2400 gr/mm, where the 1800 gr/mm is most commonly used. A 10x (0.1 N.A.) and 100x (0.9 N.A.) objectives are available. An automated XYZ stage controls sample positioning and mapping procedures. Calibrations are performed daily and ambient room temperature is recorded every 5 minutes. Temperature changes can affect the measured positions of the Raman bands.
- X-ray Fluorescence Microscope The micro-XRF analyzer (Horiba XGT-7200) is used for single point, multi-point, hyperspectral mapping analysis, and transmitted X-ray imaging. The spatial resolution of the instrument is adjustable by means of computer-controlled switching between the 50 micron and 1.2 mm X-ray guide tube. Dual vacuum modes (full and partial) allow for solid and liquid analysis. For liquid analysis, then a vacuum is applied to the detector and X-ray optics while the sample chamber is maintained at ambient pressure. The elemental range is from Na to U, and Rh target is used with a maximum tube power at 50 kV and 1 mA.
- X-ray Diffraction - Single Crystal The Rigaku R-Axis II is used to determine the atomic structure of crystals. Crystals typically need to be less than 300 microns on edge, and larger than 5 microns on edge. The R-Axis II also can do powder diffraction of single crystals or aggregates of crystals that would normally be too small for dedicated powder diffraction instruments.
- X-ray Diffraction - Powder The Proto AXRD is a low power (600W, copper) X-ray powder diffractometer with a 6-sample multi-stage sample auto changer. The auto changer rotates the sample during data collection to help increase powder averaging statistics. The AXRD is equipped with an energy discriminating silicon drift detector, which can also be used for XRF analyses. Data from this instrument are used for mineral phase analysis as well as Rietveld refinement in some cases.
Search our Collections
Search the collection by name, variety, or locality.
Dr. Celestian's main research goals as a mineralogist and geochemist are to probe the secrets of how Earth materials grow and react in their environments, and to take that understanding to predict and design new materials for environmental and industrial applications.
Dr. Kampf joined the Natural History Museum staff in January 1977, immediately after earning his Ph.D. in mineralogy and crystallography from the University of Chicago.
Alyssa received her bachelor’s degree in Geological Sciences from the University of Washington and her master’s degree in Geological Sciences from Brown University.
For information on how to join or renew your membership with the Gem and Mineral Council, contact us at 213.763.3326 or by e-mailing Dr. Aaron Celestian, Curator of Mineral Sciences, at email@example.com or Alyssa Morgan, Mineral Sciences Collections Manager, at firstname.lastname@example.org.
Follow us on Instagram @nhmla_gems.