Gems in the Smithsonian Institution

In Short

This book provides a foundational overview of gemology through the lens of the Smithsonian Institution’s National Gem Collection. It explains how gems are defined, categorized, and fashioned, while detailing the complex physical characteristics—such as specific gravity, light refraction, and chemical composition—that distinguish one species from another. By exploring the history of the collection alongside the lore and science of minerals, the text offers a clear, objective look at why certain stones have captivated human interest for millennia and how modern science identifies the authentic from the synthetic.

The Story

The narrative begins with a definition of what constitutes a gem: a combination of beauty and durability. While thousands of minerals exist, only a small fraction possess the qualities necessary to withstand the rigors of being worn as jewelry. The text traces the evolution of the National Gem Collection, which grew from modest displays at late 19th-century expositions into a comprehensive repository. It emphasizes that this growth is largely the result of public-spirited donors who have contributed individual stones and endowments to ensure these treasures remain accessible to the public.

Moving from the history of the collection to the science of the stones, the book dissects the physical properties that determine a gem's value. It explains the metric carat as a unit of weight and explores the concept of specific gravity, which allows experts to identify gems by comparing their density to water. Crucially, the discussion shifts to how gems interact with light. It explains why stones like sapphire and beryl derive their color from trace chemical impurities, a phenomenon known as being allochromatic, while others like garnet are idiochromatic, colored by their very essence.

The text then turns to the artistry of the lapidary. It notes that while nature provides the rough material, the skilled artisan is responsible for unlocking a gem’s inner brilliance through faceting. The discussion of "gem substitutes" follows, providing a pragmatic look at how the rarity and cost of natural stones have spurred centuries of imitation. It differentiates between assembled stones—such as doublets—and modern synthetic creations grown in laboratories. The text maintains that while synthetic stones pose a challenge to identification, their existence does not diminish the prestige of natural, earth-formed specimens.

A significant portion of the book is dedicated to "gem lore," detailing the historical and cultural weight placed on stones. It charts the symbolic connections between gems and the Twelve Tribes of Israel, the Apostles, and the signs of the zodiac, highlighting how these superstitions have shaped human interactions with minerals for ages.

Finally, the text serves as a catalog of the principal gem species. It offers a structured breakdown of diamonds, pearls, corundum, beryl, topaz, opal, spinel, quartz, chrysoberyl, tourmaline, zircon, spodumene, and jade. Each section explains the specific chemical makeup and unique optical characteristics of the stone, often noting the geographical regions where they are mined. It concludes with an acknowledgment that the collection is a living entity; it is constantly shifting as new acquisitions are made and older items are retired, ensuring the Smithsonian remains a vibrant space for both scientific study and public wonder.

How It Unfolds

The foundations of gemology The narrative establishes the criteria for what makes a stone a gem, specifically the balance between aesthetic appeal and physical resilience. It provides a brief institutional history, tracing the Smithsonian’s collection back to its origins in the late 1800s.

The science of properties The discussion pivots to technical definitions, explaining how carat weight, specific gravity, and the manipulation of light define a gemstone’s identity. It categorizes stones based on their chemical composition, illustrating how trace impurities create the vibrant colors found in species like beryl and corundum.

The art of shaping The focus shifts to the human element, detailing the evolution of lapidary techniques from simple polishing to the precision of modern faceting. This section distinguishes between natural stones and the various categories of substitutes, from historic glass imitations to contemporary lab-grown synthetics.

The legacy of lore The book examines the historical intersection of geology and human belief, listing the stones associated with ancient religious and astrological systems. This provides context for why certain gems have traditionally been held in higher esteem than others.

The species guide The latter half acts as a taxonomic survey of major gemstones, providing a comprehensive breakdown of each species. It details the unique characteristics—such as the pleochroism of spodumene or the toughness of jade—that define the world's most notable minerals.

The People

While the book is a scientific survey rather than a biographical narrative, it centers on the contributions of key figures who shaped the field. Prof. F. W. Clarke appears as the foundational figure, having curated the initial exhibit of American precious stones that laid the groundwork for the National Gem Collection. Dr. Joseph Leidy is recognized for his significant contributions to the collection’s growth in the late 19th century, which allowed for a more substantial showing at the 1893 World’s Columbian Exposition. G. F. Kunz, the namesake of the mineral "kunzite," is mentioned as a vital American gemologist whose work helped define the classification of spodumene. Through these names, the text highlights the collaborative nature of museum curation, where the work of scientists and private donors converges to preserve geological history for the general public.

In Its Own Voice

"To be used as a gem, a mineral species must have durability as well as beauty."

This observation, found in the opening chapter, establishes the fundamental criteria for why only a small fraction of known minerals are considered suitable for jewelry.

"The National Gem Collection had its beginning in 1884 when Prof. F. W. Clarke, then honorary curator of the Division of Mineralogy, prepared an exhibit of American precious stones as a part of the Smithsonian Institution’s display at the New Orleans Exposition."

This sentence marks the formal origin of the collection, situating its development within the context of 19th-century public expositions.

"There are records of glass and ceramic imitations of gems as early as 3000 B.C."

This historical fact serves to temper the reader’s surprise at modern synthetic stones by showing that the human impulse to replicate gems is as old as civilization itself.

What It's Really About

At its core, the book explores the tension between nature’s chaotic geological processes and humanity’s desire for order and beauty. It argues that a gem is not merely a mineral, but a cultural object defined by its scarcity, its optical properties, and its historical associations. The text probes the question of authenticity: if a lab-grown stone is chemically identical to one mined from the earth, what is the source of the natural stone's superior value? By grounding its arguments in chemical formulas and physical measurement, the text pushes the reader to see beyond the surface-level shimmer of a stone, inviting them to consider the environmental pressures that formed it and the human ingenuity required to reveal its hidden character.

Why Read It Today

This book is a perfect companion for the visitor who walks through a museum display and finds themselves wondering, "How do they know that’s real?" It offers the quiet satisfaction of a well-organized reference manual, stripping away the mystery of gemstones to reveal the fascinating, often surprising chemistry underneath. Readers who appreciate precision and clarity will find its systematic approach deeply rewarding.

However, a reader should be aware that this is a product of 1965. Its style is functional and dry, lacking the conversational flair of modern popular science writing. The text assumes a certain level of interest in mineralogy and does not shy away from technical jargon like "allochromatic" or "pleochroism," though it defines these terms clearly as it goes. It does not attempt to be a glossy coffee-table book; instead, it is a serious, straightforward report from the desk of a curator. For those who want to understand the why and how of the world’s most precious stones, it remains an indispensable, unpretentious guide. You will leave this book with a much sharper eye for detail and a genuine appreciation for the intersection of geology and human history.