American Museum of Natural History Research Library
author: American Museum of Natural History

Allison and Roberto Mignone Halls of Gems and Minerals; Mignone Halls of Gems and Minerals
birth: 2021 June 12
death: present
Permanent exhibition. Opened June 12, 2021. The Allison and Roberto Mignone Halls of Gems and Minerals tell the story of how the vast diversity of mineral species arose on our planet, how scientists classify and study them, and how we use them for personal adornment, tools, and technology. The galleries feature more than 5,000 specimens from 98 countries. The complete redesign of the former Morgan Hall of Gems and the Harry Frank Guggenheim Hall of Minerals was made possible by Allison and Roberto Mignone. Organized by Curator George E. Harlow of the Museum’s Division of Physical Sciences.
The scientific framework for the Halls is mineral-forming environments, focusing on the five conditions and processes in which minerals form: igneous, pegmatitic, metamorphic, hydrothermal, and weathering. As part of this construct, the Halls introduce a concept that has developed over the past 15 years: mineral evolution. Recognizing that there were no minerals at all for hundreds of millions of years after the Big Bang, the concept explains how our planet today came to host more than 5,500 mineral species. The process began with supernovae infusing the universe with more and heavier elements, which could combine into minerals. The formation of planets enabled their differentiation, mostly in the form of molten rocks heading to the surface. On Earth, as new mineral forming environments arose—with the accumulation of liquid water, for example, or the introduction of free oxygen into the atmosphere by the first photosynthetic organisms—minerals diversified in color, texture, and chemical composition. Organisms contain, produce, and use minerals, and new minerals have formed because of life.
The 11,000-square-foot-halls include original gems, such as:
* 563-carat Star of India sapphire
* 632-carat Patricia Emerald
* 110-carat diamond Organdie necklace designed by Michelle Ong for Carnet
New specimens include:
* 35-million-year-old metasequoia section
* Petrified dawn redwood from the Cascade Mountains
* 9-pound almandine Subway Garnet discovered under Manhattan's 35th Street in 1885
* Tarugo, 3-foot-tall elbaite tourmaline
Other hall highlights include:
* Singing Stone (blue azurite and green malachite)
* Fluorescent rock wall-sized panel sourced from Sterling Hill, New Jersey
* Yellow fluorite from Spain
* Amphilobite rock containing almandine garnet crystals from Gore Mountain, New York
* Dravite tourmaline crystals, a large 1.8-billion-years-old assemblage
* 5-foot beryl crystal section from Bumpus Quarry, Maine