Blogs from our Scientific Researchers

The Carnegie Institute has been in existence for 125 years and is one of the greatest architectural buildings ever designed in Pittsburgh. In 1985, Carnegie Institute President Robert Wilburn invited Dr. Cynthia R. Field, the Smithsonian’s Architecture Historian, to assess the artistic value of the museum. He asked, “what do you think is the most valuable specimen or painting in the museum?” She said, “The Building Itself is the Greatest Object of the entire Museum Collection” (Fig. 1).

Fig. 1: Carnegie plaque

The internationally-famous architect, I.M. Pei, who designed the Louvre’s glass pyramid that sits in the Louvre’s central courtyard in Paris, France, opined, “Architecture is the very mirror of life. You only have to cast your eyes on buildings to feel the presence of the past, the spirit of a place; they are the reflection of society.” In 2018, Architecture Digest ranked the Carnegie’s Grand Staircase the 8th best museum staircase in the world. The Grand Staircase was built by the Pittsburgh architectural firm of Alden and Harlow at the apex of America’s Gilded-Age building boom. During my research, I discovered that the architects employed multicolored classic marbles and fossil limestones in the interior design from Algeria, Croatia, Greece, France, Ireland, Italy, and the United States. The commission to build the Grand Staircase in 1907 incorporated two classical French fossil limestones in the columns and pillars, floor tiles, steps, walls, balconies, and water fountains. This monumental Beaux-Arts style staircase is modeled after the L‘Opéra Garnier ‛a Paris, Grand Staircase in France, c. 1875, and was visited by a French Delegation with Andrew Carnegie (Fig. 2). The architecture described as Beaux-Arts was taught at the École des Beaux-Arts in Paris, from the mid-19^th century until 1900. It drew upon the principles of French neoclassicism and used modern building materials, i.e., iron and glass. And as such, it became a preferred architectural style in the United States from 1895 until 1910 in cities such as, Boston, Chicago, New York City, Pittsburgh, and Washington D.C.

Fig. 2: French delegation and Andrew Carnegie

In 2019, The Carnegie’s Grand Staircase and Music Hall Foyer were recognized in the book La pierre de l’Échaillon Une histoire locale, une renommée international for the use of Échaillon jaune (yellow) ornamental stone in the museum’s columns, pillars, and walls (Fig. 3). This book was published by S.P.I.A. (Sauvegarde du Partrimoine Industriel d’Autrefois, a historical society founded by Jean Paul Rey, president) (Fig. 4).  In the book, they describe how a small French village of l’Échaillon, pronounced Esh-ee-own, received recognition for its white marble (a limestone) used by famous French architects in 64 classic buildings and sculptures from 1875 to the early 20^th century (Fig. 5).  I first met Jean Paul in October of 2016, when I was invited to give a presentation at an S.P.I.A. meeting on my research on the Carnegie’s l’Échaillon.  The meeting was held in an old schoolhouse in the village of Saint-Quentin-sur-Isère, Département de Isère, in southeast France.

Fig. 3: The Grand Staircase

Fig. 4: Jean Paul Rey and Albert D. Kollar

Fig. 5: Book cover

The French Limestones in the Carnegie’s Architecture

The Carnegie building stones research project progressed significantly, once we obtained the digital images of the architect’s blueprints from the Carnegie Museum of Art’s Architecture Department. With the assistance of my co-authors, Rich Fedosick and Kay Hughes of the Section of Invertebrate Paleontology, we examined the blueprints to understand the architects Marble Index terminology (Fig. 6). Eventually, we were able to interpret and recognize the location of the two French limestones based on the Marble Index letters, E for Échaillon and H for Hauteville. From a nonscientific perspective, the architects considered the Carnegie’s interior stones to be marbles. However, the geological definition of a marble is when a rock defined as a limestone or dolomite is subjected to high heat and pressure from geologic forces forms a metamorphic rock.  The six stones listed in the Marble Index as marbles, are limestones, a sedimentary rock enriched with fossil seashells. The characteristic rudist fossils and yellow color that distinguish the Échaillon stone are found in the 18 pillars and the 22 columns that rise 3.8 meters or 12.5 feet about the Grand Staircase, and in the walls of the Music Hall Foyer (Fig. 7).

Fig. 6: Marble index E and H letters

Fig. 7: Échaillon fossils

The other French limestone used in the Carnegie is Hauteville. This limestone was quarried from the Plateau d’Hauteville in the Ain Department, in eastern France. I visited this quarry in 2016 to investigate the geology of the quarry operation, to uncover evidence of the common fossil snail Nerinea in the quarry rock (Fig. 8), and to learn more about the cultural history of the region (Fig. 9).  The Hauteville limestone was used in the Grand Staircase walls, balcony features, water fountains, vestibule steps, and as floor tiles. Other locations include, the Hall of Sculpture and Hall of Architecture floors, the walls along the grand hallway, the Music Hall vestibule floor, the Founder’s Room vestibule floor, the floor and steps in the Smoking Room (now offices), the Forbes Avenue vestibule entrances to the music hall, carriage drive, and museum and fine arts. Moreover, the Hauteville floor tiles are distributed throughout the Carnegie Library of Pittsburgh main entrance corridors. The Hauteville stone is beige in color and contains many visible fossils, none more distinctive than the robust Nerinea, a 12.7 cm/5-inch-long snail that serves as the index fossil for the limestone identification (Fig. 10).

Fig. 8: Hauteville Quarry fossil snail

Fig. 9: Hauteville directional signs

Fig. 10: Nerinea snail in Carnegie floor

Introduction to the l’Échaillon Carrières

There are three carrières or quarries in the Vercors cliffs located in the Isère River Valley that were excavated for White Echaillon or “Echaillon blanc,” Yellow Echaillon or “Echaillon jaune,” and Pink Echaillon or “Echaillon rose” during the 19^th and early 20^th century (Fig. 11).  These unique color combinations became popular for various interior and exterior architecture features in 194 buildings in western Europe, North Africa, and the United States. In 2016, Jean Paul Rey and members of S.P.I.A. led me on a field trip to the abandoned classic l’Échaillon white quarries (Fig. 12). We explored what is thought to be a 2,000-year-old Roman quarry and walked through a maze of underground caverns and narrow tunnels that contained abandoned mining equipment.  The other two Echaillon carrières are located several kilometers south in the small villages of Lignet, where the Pink Echaillon was quarried (Fig. 13) and Rovon, where the Yellow Echaillon was excavated (Fig. 14).

Fig. 11: Echaillon quarries locations, S.P.I.A.

Fig. 12: Visit to Echaillon

Fig. 13: Lignet Quarry Marker

Fig. 14: Rovon quarry

Cularo, Grenoble, and the white l’Echaillon stone

A fortuitous discovery was made by S.P.I.A. for their book while searching for evidence of the white l’Echaillon in the Gallo-Romans era 4th century Cularo or Grenoble, France today. In the Saint Laurent crypt that is preserved many meters below the modern-day street level tramway, a white capitol on top of a white limestone column was identified as l’Echaillon. This white capitol stone is presumably from the Roman quarry adjacent to the white l’Echaillon underground caverns. When Emperor Gratian ruled the Roman Empire from 367 to 383 A.D., he renamed Cularo after himself. Cularo thus became Gratianopolis, which through a later phonetic shift became Graignovol and then Grenoble. Although hard to find among the narrow streets and passageways of Grenoble, is a section of a Roman wall that once encircled Cularo, a portion of which is protected by a fence. This historic wall can be seen at Passage Sainte-Claire on the corner of Rue Lafayette, in the central city of Grenoble (Fig. 15). I suspect some of the white cobbles embedded in the wall may have their origin from the white l’Echaillon Roman quarry. Undoubtedly, more research will be necessary to make an affirmative conclusion.

Fig. 15: Roman wall

“Geology of the l’Échaillon Carrières”

The drawing of a new geologic map on the l’Echaillon carrières by Professor Thierry Dumont of the Université Grenoble-Alpes, confirms stratigraphically, the ages of the three limestone quarries. Among the three, the white Echaillon limestone is late Jurassic in age, whereas the pink Lignet and yellow Rovon limestones are early Cretaceous in age. The formal geologic name for the rose and yellow limestones is the Urgonian Formation. Fossils are abundant in the three limestones. Dr. Claudie Durand of Le musèum d’Histoire naturelle de Grenoble (Fig. 16) curated a diverse collection of 163 species of invertebrate fossils from l’Echaillon first published in 1919. Geologically, the three limestones were deposited in the tropical Tethys Seaway a circum-equatorial ocean of the Mesozoic Era. The strata form the Vercors carbonate platform, a buildup of late Mesozoic rudist (bivalve mollusk) reefs spanning 25 million years of evolution from (late Jurassic 140 million years ago to early Cretaceous 165 million years ago) (Fig. 17).  

Fig. 16: Dr. Claudie Durand

Fig. 17: Rudist (bivalve) reef fossils

The Rovon carrière provenance and fossils

The primary goal of this research is to define the geology and authenticate the specific provenance of all marbles, fossil limestones, sandstones, and the singular igneous granite rock used in the Carnegie building. The search for the provenance of the Carnegie’s yellow Echaillon was initiated in December of 2017 by Jean Paul Rey, when we were introduced to the Forman of the modern-day Rovon quarry. After a long discussion about our objectives, he granted permission to visit the old quarry. As darkness fell, we met with a local farmer who directed us to the quarry location in the Vercors cliffs that rise some 538 meters above his snow-covered field (Fig. 18).  

Fig. 18: Verors cliffs and old Rovon quarry

In October of 2018, the S.P.I.A. team pre-arranged to have several 4-wheel trucks transport ten people including Professor Fabienne Giraud-Guillot of the Université Grenoble-Alpes to the Rovon quarry. We ascended the long steep road that ended some 500 m from the main quarry. Surprisingly, the quarry was filled with massive limestone boulders that were cut by mechanical wire saws from the cliff rock (Fig. 19). Such large boulders make it virtually impossible to break with small hammers. For actual fossil collecting purposes, it is better to search for smaller size rocks to break apart (Fig. 20). This past October, transport to the Rovon quarry riding in a 55-year-old Russian built farm tractor was a treat (Fig. 21). And the fossil collecting was a success with 21 complete specimens collected for the museum of the diagnostic Caprina rudist bivalve clam (Fig. 22). The shape of these fossils closely resembles the fossils preserved in the Echaillon limestone in the Grand Staircase and Music Hall Foyer. Additional geologic data is being reviewed by colleagues from the Geology Department at the University of Zagreb in Croatia and the University of Ireland at Galway.  

Fig. 19: S.P.I.A. team

Fig. 20: Collecting fossils

Fig. 21: Russian tractor

Fig. 22: Caprina rudist clam

“Carnegie’s Grand Staircase in the 21^st Century”

A study published this month by the BMJ, formerly The British Medical Journal, suggested that “when people of all ages participate in the arts and visit museums once a month or even every few months, they are likely to be more engaged in the world and may actually live longer.” Years ago, the Oscar winner actor Russell Crowe was in Pittsburgh, and he was asked what he did on his days off. In reply, he said, “I ride my bicycle to look at buildings and the architecture of the city.” I. M. Pei states, “Architecture brings people together.” I agree.

Maybe it’s time to reconsider how the Carnegie’s Grand Staircase is promoted to the public at large. For instance, the current arrangement of the free-standing dioramas situated on the first floor, awkwardly impede the flow of patrons walking among the pillars, columns, and the taking of photographs of the Grand Staircase.  Moreover, the placement of these dioramas detracts from the visual enjoyment of the famous John White Alexander multicolor murals. An artistic feature of the murals is their connection to the stone colors to enhance the first and second floors architectural features. The best vantage points to see this fabulous spectrum of color is from the third-floor balcony looking down to the first and second floors.

The Carnegie Museum of Art (Museum of Fine Arts) will be celebrating its 125^th Anniversary in the fall of 2020. The Grand Staircase was designed as the showcase entrance to the Museum of Fine Arts for Pittsburghers of the early 20^th Century. One hundred and twenty-five years later, perhaps, this world-class space can once again establish a new generation of museum patrons and become the destination as a place to be for its cultural and intellectual heritage.  And don’t forget, this staircase can be an Instagram-worthy site for a family portrait to encourage our younger audiences to visit too.

Albert D. Kollar is the Collection Manager in the Section of Invertebrate Paleontology at Carnegie Museum of Natural History. Museum employees are encouraged to blog about their unique experiences and knowledge gained from working at the museum.