Print Study Room: Natural Resources

“Introduction to Natural Resources” with Department Chair of Geosciences Jennifer Cholnoky

“If it’s not grown, it must be mined.” Mineral resources (metals, industrial minerals, gems, and building materials, for example) are the foundation of many national economies and have complicated and contributed to geopolitical and environmental conflicts throughout history. In this course, students learned about the formation and distribution of mineral resources and about the impact exploration and extraction of these materials has had on man and earth.

Students researched these connections in order to write labels for objects in the Tang collection that contain mineral resources as a material. You can read the results of their research below.

Student Responses

Expand all
Collapse all
Natural Resources Spring 2022
Unrecorded artist, Ginger Jar, ca. 1800, glazed porcelain, 12 x 8 ¼ x 8 ¼ inches, Tang Teaching Museum Collection, Lucy Skidmore Scribner Decorative Arts Collection, LS101
Avery Blake ’23 and Max Volk ’24

This white porcelain Ginger Jar is an intricate representation of early 19th-century Chinese porcelain ceramic work. The jar has three sections, the base, the decorated jar, and the lid. The base notably was made separately from the vessel, most likely boxwood, commonly used in Chinese wood sculptures. The specificity of the imagery on the porcelain utilizes a spectrum of pastel earth tones- such as blue, yellow, green, and red. A carved jade tops the lid.

Chinese porcelain includes kaolin, porcelain stone, feldspar, and quartz. Porcelain stone consists of a range of decomposed raw materials such as micaceous or feldspathic rocks (known historically as petuntse). Kaolin is an exceptionally soft white clay from kaolinite originating from China and exported to Europe during the 1700s.

White jade was introduced to China from Myanmar (Burma) in the 18th century. The material was mined in the mountains by hand and collected in streams. Jadeite is exceptionally hard and cannot be carved with traditional metal tools. Thus, the material was worn down using carborundum sand (silicon carbide) alongside a soft tool or diamond. Jade forms in deep earth crust under high-pressure hydrothermal systems. Here the dissolved minerals in escaping water fill and deposit into cracks from tectonic subduction areas and hydrothermal alteration zones.

Unrecorded artist, title unknown, ca. 1850s, hand-tinted daguerreotype, intact case, 3 5/8 x 6 3/8 inches, The Jack Shear Collection of Photography at the Tang Teaching Museum, 2015.1.500
Claire Loos ’22 and Sara Powers ’25

Daguerreotypes, such as this one depicting a seated woman, were popularized around the 1840s. A daguerreotype is an early form of photography invented in France that involves exposing a silver-plated copper sheet to mercury vapors. Creating a daguerreotype is a natural resource-intensive process, using at least 7 different minerals and chemical substances.

The process is as follows: a pure copper sheet is coated with silver then is sealed in a lighttight box and exposed to iodine and bromine vapor until the silver-coated copper sheet turns yellow. This process is called sensitization. After sensitization, the yellow sheet remains in a lighttight container and is transferred directly into a camera. When the exposure is made the camera lens captures differences in light onto the sheet. Then, the newly exposed sheet is placed over hot mercury fumes, a highly toxic substance, to develop the image. Lastly, the sheet is placed in a solution of sodium chloride or salt and treated with gold chloride for image polishing.

Other natural resources like brass and glass are also present in daguerreotype cases, such as with a brass mat used to secure the photograph and the glass protecting the image.

Charles Long, Miranda, 1992, cast bronze, 16 x 34 x 16 inches, Tang Teaching Museum collection, purchased in honor of Morgan Leger Rosenberg, Class of 2009, 2008.13.3a-b
Maxwell Baskins ’23 and Malin Zucca ’24

This sculpture was made using lost wax casting, a metal casting technique that is over 6,000 years old. The process starts with a sculpture made out of clay, which is used to create a plaster mold. That mold is then filled with a layer of wax, and the resulting hollow wax replica is used to create another mold, and when the wax is melted out, it is cast in molten bronze.

Bronze itself is a mixture of copper and tin, but often includes trace amounts of other metals such as aluminum, phosphorus, or zinc, which are heated into a liquid and mixed together to form the alloy. Copper can be found in copper porphyry deposits, a type of ore deposit found at convergent boundaries. These deposits form when an oceanic plate subducts under a continental plate, causing liquid magma to rise. As the magma starts to cool, metals start to precipitate out and form multi-layered deposits. Tin is usually found in vein deposits. Vein deposits occur when magma is forced upwards into cracks in the crust where circulating groundwater deposits various minerals. These deposits often occur at divergent boundaries where there is a lot of strain and rifting from the plates moving apart.

Issabel Case Borgatta, Untitled Figure 2, n.d., white stone on stone plinth, 23 x 8 x 5 inches, Tang Teaching Museum Collection, gift of Mia Borgatta, Paola Borgatta, and Francesca Borgatta, 2018.2
Liam Gislason ’24 and Lila Norton ’24

Untitled Figure #2, by Isabel Case Borgatta, is a sculpture made of marble. Borgatta traveled to Greece and the Yucatan Peninsula and became highly influenced by the sculptures she saw; these works later inspired her to return and collect stone of her own. The artist felt connected to each stone and its individual unique qualities, appreciating the finality of stone. Marble is a favored medium to sculpt. Before it is quarried it is soft and easy to work, but after time it hardens and becomes extremely dense, not to mention it has beautiful shades and patterns.

Marble is a metamorphic rock, which forms after limestone is exposed to high pressure and heat. Under metamorphic conditions, calcite minerals in limestone crystalize, forming an organized interlocking mass. The purity of limestone ultimately determines the whiteness of the marble created. If limestone contains other minerals besides calcite, such as micas, quartz, pyrite, or iron, the marble created will have strokes of black, brown, pink, or yellow. Marble is often found at convergent boundaries where the heat from subducting oceanic plates creates metamorphic conditions for the continental crust. Marble can also form through contact metamorphism, where a magma body heats up surrounding limestone to induce metamorphism.

Louis Comfort Tiffany, Tiffany Favrile Vase, 1921, favrile glass, 8 x 2 ¾ inches, Tang Teaching Museum collection, gift of Anne W. Wells, 2015.20
Emerson Neely ’25, Caroline Rogers ’24, and Cranac Surpris III ’23

The Tiffany Favrile Vase ia an example of Art Nouveau glassware made around 1921, in Queens, NY. This blown and tooled Favrile glass vase features a blue iridescent chrome color and a thin stem. On the underside of the vase around the base and under the pontil mark (evidence of the glass being removed from the punty rod during creation), “1262-4715M L.C.Tiffany Inc. Favrile’‘ is written in black.

The Favrile technique involves the incorporation of metal oxides to molten glass to create an iridescent luster. This vase likely incorporates cobalt, which is typically mined from arsenide and sulfide minerals. While the origin of the sand aggregates and Tiffany’s source of materials used to create this specific vase is unknown, the majority of blown glass is of a borosilicate composition. Borosilicate glass is typically made of a mixture of silicate (quartz) sands, boric oxide, sodium oxide, and small amounts of aluminum and potassium oxides in an effort to make it more resistant to drastic temperature changes.

Louis Comfort Tiffany is credited for patenting favrile glass and was the Artistic Director and son of the founder of Tiffany Studios. It is generally believed that Louis Comfort Tiffany was the visionary behind most Tiffany glass works, while he had a team of artists and chemists execute his ideas. Two of his primary chemists, Arthur Nash and his son Leslie, kept a leather notebook of chemical recipes for the glass which include claims that they were the creators of favrile glass, and not Tiffany himself who allegedly took credit for the formula.

Derby Silver Company, Serving Tray, ca. late 19th century, silver plated copper, 11 x 6 ¼ x 8 inches, Tang Teaching Museum Collection, gift of Elizabeth Jones Estate, 1995.8
Xander Farmer ’24 and Adam Schnitzer ’24

The Derby Silver Company was based in Derby, CT, and produced metal wares from 1872 to 1933 when the plant was forced to closed during the Great Depression. Their silver and other metals (such as copper and gold) were sourced from a deposit in Meriden, Connecticut. In 1898, Derby Silver merged with the International Silver Company in Meriden, Connecticut.

This tray is quadruple-plated with silver, meaning that four layers of silver are electrochemically plated to the copper frame. This design was used to strengthen household copper items, as well as to protect the metal from corrosion making for a long-lasting product. Additionally, silver-plated goods allowed for people to have items that looked like silver without paying for sterling silver goods. The center part of the tray features unique engraving techniques with a rose-colored gold appearance, likely due the copper underneath.

Although layering helps increase longevity, tarnish has formed in many places. The discoloration forms through processes such as oxidation and tarnishing. Silver sulfide compounds form as a result of the silver coming into contact with sulfur, having had exposure to air or moisture.

Unrecorded artist, Jaguar pendant, ca. 1200-1500, gold, 1 ½ x 1 x 1 inches, Tang Teaching Museum collection, Moreen O'Brien Maser, Class of 1926, Memorial Collection, ML1982.185
Nicco Miani ’24 and Christy Phillips ’24

This solid gold pendant was gifted to Skidmore College in 1982 as a part of the Moreen O'Brien Maser Collection. It is believed that this piece originated in South America or Central America between the years 1200-1500. During the Mesozoic and Cenozoic ages, the west coast of South America was the perfect location for gold deposits. During this period, approximately 200 million years ago, the coastal zone was situated on a mountainous area that was formed during an earlier orogeny. Conditions created the ideal environment in which the lithospheric mantle, rich in minerals, could be extruded through faults and shears forming massive and widespread gold deposits.

This pendant was most likely made with a wax and clay mold, also known as the lost wax technique. The figure (in this case a jaguar) would be sculpted out of wax and covered with a clay charcoal mixture. Once the clay dried out, it would be heated up so the wax melted out, leaving a hollow clay mold. Liquid gold would be poured into this mold and the clay would be broken to reveal the golden pendant.

Veronica [Ohkay Owingeh (formerly San Juan Pueblo)], San Juan Pot, ceramic earthenware, 2 ½ x 4 ½ x 4 ½ inches, Tang Teaching Museum collection, gift of the Skidmore Biology Department, ND327
Kyle Fink ’22 and Jenna Wilhelm ’22

This pot is from the Ohkay Owingeh Tribe, meaning the place of the strong people. This tribe resided twenty-five miles north of Santa Fe, New Mexico from 1589-2005. For the tribe, pottery was important culturally, historically, and economically. Specific to each tribal community, the pottery techniques of the Ohkay Owingeh people were likely passed down through families or by oral traditions.

Ceramic pieces such as this were handmade using clay coils and dried sand, washed down with water, and polished with slips. Slips are a fine clay material that seal and smooth the pot. Each pot was painted and then fired. The paint pigments were derived from naturally occurring minerals, such as iron oxides that created the red-orange color of the pot. These minerals were derived from the San Juan rock formation, which consisted primarily of sandstones and clays. This pot in particular has a few clues to its creator or its previous use, specifically, a signature of the name “Veronica” is located on the unfinished foot of the pot, as well as the number “3”, possibly indicating it was previously sold in a market.

Unrecorded artist, Sejant Buddha and Prangs, ca. 1350-1600, stone architectural relief on wood stand, Tang Teaching Museum collection, Moreen O'Brien Maser, Class of 1926, Memorial Collection, ML1982.279
John Chidekel ’22 and Katsy Weber ’23

This limestone relief was originally a portion of an architectural facade. It depicts five Buddha figures seated in a cross-legged position. They sit within delicately carved prangs, with smooth and small curves present throughout. Prang architecture is characterized by intricate detailing with a conical tapering tower, as echoed in this relief.

In this example, there is a piece missing from the top of one prang and signs of weathering along the back and sides. There is a script along the bottom which is unidentified due to weathering, age, and a lack of linguistic knowledge. The face of the relief has been smoothed, creating fine details along the figures and the structures and helping separate the relief from the base rock. Limestone is well suited to be smoothed as it is a soft rock that is easy to sand.

The stone for this relief likely came from limestone karsts in Southeast Asia. These limestone deposits were formed from the sedimentation of microorganisms within warm seas during the Paleozoic era. Due to tectonic activity, terranes were formed from an accretionary wedge, suturing these limestone deposits together.

Natural Resources Spring 2020
Ansonia Clock Co., mantel clock, 19th-20th century, glass, brass, steel, jade, 12 ¾ x 7 ⅜ x 6 ¼ inches, Tang Teaching Museum, gift of Patricia Hart, 1994.43
Zoe Pagliaro ’20, Katie Garofalo ’20, and Olivia Kupiec ’22

The mottled viridescent base and top of this clock are characteristic of the gemstone jade, which is derived from the mineral jadeite. This mineral is commonly recognized for its colorful hues that range from pale apple to forest green. Jadeite forms in metamorphic rocks deep in Earth’s crust that are under high pressure but low temperatures. This most commonly occurs in subduction zones or tectonic regions in which the ocean floor sinks beneath a continental land mass.

The gold colored frame and gears are made out of brass, a mixture, or alloy, of the elements copper and zinc. The more zinc that is added to the melted copper, the stronger and less moldable the brass becomes, creating a material ideal for forming the functioning gears of an ornate clock. Copper is formed at subduction zones where hot briny water dissolves and transports copper and concentrates it in the crust. Zinc is commonly deposited in vein shaped cracks in continental rock as the temperature cools and pressure decreases when hot magma rises.

The darker, internal framework of the clock is steel, an alloy of iron and carbon. Most iron is extracted from Banded Iron Formations, ores that formed during the Great Oxygenation Event 1.8-2.6 billion years ago; iron molecules already present in the ocean bonded with newly introduced oxygen from the first photosynthesizing plants.

Regis Brodie, untitled, 1973, salt-fired ceramic with luster overglaze, 7 x 4 ⅞ x 4 ⅞ inches, Tang Teaching Museum, gift of the Estate of Wallace B. Moore, 1994.35
Liana Heath ’22 and Simone Rothberg ’20

Regis Brodie, born in 1942, worked as a professor in the Art Department at Skidmore College for 41 years. During his time at Skidmore, Brodie created a series of ceramic works that were exploratory in nature, created for artistic observation rather than a functional use. Brodie created this Untitled work using a technique called salt-fired glazing. In this process, the potter throws salt into the hot kiln, which reacts with silica in the clay to produce sodium silicate. This creates a glassy visual quality, as well as the orange peel-like texture with small indents as can be seen on this piece.

Clay deposits form from chemical and physical weathering of silicate bearing rocks over a long period of time. There are three types of clay used for pottery: earthenware, stoneware, and porcelain. We suspect that this piece is made from earthenware clay, as this type is usually used for decorative pieces and holds the original glaze color for a long time. The salt in the glaze is common NaCl (the same as table salt). The glaze may be sourced from cobalt oxide, used in conjunction with iron and manganese, to produce the blue color.

Keith Edmier, Cycas revoluta bulbil, 2003, acrylic, cast urethane on basalt base, 8 ½ x 13 x 16 inches, Tang Teaching Museum, gift of Marianne Boesky, 2015.38.1
Isaac Bardin ’20 and Jaclyn Finger ’23
Cycas revoluta bulbil is titled after the cycad, an ancient plant with stiff green leaves which has survived for millions of years with few changes. The sculpture base was formed from basalt, melted into lava in a furnace at 1,000 degrees Celsius and poured into a mold. Basalt is commonly found in ocean basins as fast-cooling lava, but in the studio Edmier slowed down the cooling rate by burying it in insulators like sand and wood shavings to produce a glassy-smooth texture. Once cooled, the sculpture base emerged from the mold as a striking wavy ring, and the cast urethane plant was later attached. Cycads can reproduce asexually—Cycas revoluta bulbil addresses aspects of sexuality and symbolizes the male and female functions of reproduction, renewal and rebirth.
Artist unknown, three scholar’s rocks, n.d., stone on wood, Tang Teaching Museum, promised gift of Susan M. Yecies
Harrison Winrow ’22 and Sophia Barrett ’21

The Scholar’s Rock is a naturally occurring volcanic rock that was most likely mined or discovered during the Tang Dynasty (618-907). The type of rock is probably basalt, a mafic, extrusive, igneous rock, because of its fine-grained composition and dark coloring. Basalt, consisting of plagioclase, pyroxene, and similar minerals, forms from lava flow and igneous dikes. It is often formed near oceanic divergent boundaries, oceanic hotspots, mantle plumes, or regions of volcanic activity.

In China, exposed basalt can only be located at the geologic anomalies of the south China folds, the Wanda Mountain region, and volcanic sites in the northwest region of the country. These samples may have formed at oceanic divergent boundaries up to 250 million years ago; magma spills into an ocean basin and lithifies as the boundary pulls apart. Over an extended geologic timescale, these pillow basalt formations can be discovered exposed on continental surfaces from tectonic movement and supercontinent cycles. Oceanic hotspots cause basalt to form as magma rises from within the mantle at a particularly thin region of the asthenosphere.

Unrecorded Mbole artist, anklet, 20th century, copper alloy, 5 x 9 x 9 inches, Tang Teaching Museum, gift of Bill and Gale Simmons, 2000.1.42
Mac Dill ’20 and Anna Merrens ’20

This anklet, from the Democratic Republic of Congo, was likely used as currency or for other transactional agreements, and would have been worn on the ankle after being traded. Similar anklets have been forged in brass, however, the scratches and wear on the surface of this piece suggests that it was forged in copper.

The use of copper makes economic and geographical sense in connection to the geology of the region, as the Democratic Republic of Congo is located next to and on top of the second-largest reserve of copper, the Katanga Copperbelt.

Formed in the Neoproterozoic era, 1,000 to 541 million years ago, there are several hypotheses as to why the Katanga Copperbelt formed. Most scientists attribute the pH and saltwater located in the region at the time of creation as integral to the concentration and deposition of copper, cobalt, and nickel. Beyond these factors, compression from plate tectonics over time has been attributed to altering the structure and location of these deposits.

Unrecorded artist, figure, 1500 BCE – 300 CE, serpentine jade, 3 ⅛ x 1 x 1 inches, Tang Teaching Museum, Moreen O’Brien Maser Memorial Collection, ML1982.156
Kailey Toia ’20 and Crystal Belle ’22

This figure was carved from serpentine jade in the Olmec Empire (1500 BCE–300 CE). In Olmec cultures, pendants are carved from serpentine to protect against poison, venom, snake bites, and parasite infections.

Serpentine jade differs from traditional jadeite as it is less dense and has a lower hardness, so it is easier to carve. Although nephrite is more similar to serpentine jade, the distinction can be made by nephrite being less waxy and translucent.

It is thought the Olmec traded for serpentine with the Mokaya civilization, located in Western Guatemala. Due to the subduction zone at the Motagua fault line in Guatemala, the Mokaya civilization had access to deposits of serpentine jade.

Serpentine jade is formed when an ocean plate subducts under a continental plate. The ultramafic rocks present at the convergence zone undergo hydrothermal metamorphism. The olivine and pyroxene minerals in the rock are intruded with seawater carrying serpentine minerals, which then replace them.

Unrecorded artist, Maya-Toltec carving, 900-1200 CE, stone, 10 ½ x 20 x 8 inches, Tang Teaching Museum, Moreen O’Brien Maser Memorial Collection, ML1982.1Drew Bugna ’22 and Freddie Klaus ’20
Drew Bugna ’22 and Freddie Klaus ’20

This carving in stone from the Maya Toltec civilization (900-1200) depicts a figure in a recumbent position indicating that they are likely of high status. Adorned in accessories that also reflect status, the figure appears to be smoking a pipe. The bird-like figure resting on the figure’s shoulder pays homage to Tezcatlipoca, the Smoking Mirror, god of the nocturnal sky, god of ancestral memory, god of time and the Lord of the North, and the embodiment of change through conflict.

The stone material of this carving is most likely limestone. Limestone is a sedimentary rock, frequently formed in shallow marine environments from shells and skeletons from marine organisms. These organisms form calcium carbonate shells, and once they die these shells are broken down by waves and accumulate as sediment on the ocean floor. As these particles are compressed, they lithify into solid rock and limestone is produced. The Gulf of Mexico is a limestone forming environment, and the Toltec capital city of Tula was located on a limestone outcrop, so many artifacts from the civilization were created in this material.

Artist unknown, three scholar’s rocks, n.d., stone on wood, Tang Teaching Museum, promised gift of Susan M. Yecies
Kate Bjorklund ’20 and Oliver Wilson ’23
Scholar’s rocks first appeared in China during the Tang Dynasty (618-907). Interest in the natural environment surged with the concurrent rise of Daoism, and these prized wood-mounted stones were used to study microcosms of the universe. Most scholar’s rocks are made of limestone that once existed in the Yingde and Lingbi caves, as well as in the Quinshi Mountain mudflats of the Anhui province in Eastern China. The mildly acidic soil would help shape the stones in the mudflats. Whereas, natural water erosion and calcification processes likely sculpted the stones found in caves. In some cases, the valued qualities of the rocks were enhanced through polishing.
i
Pattern by Madeleine Welsch ’17
Inspired by the exhibition Someday is Now: The Art of Corita Kent
The Tang Pattern Project celebrates the Museum’s 20th anniversary. Organized by Head of Design Jean Tschanz-Egger, past and current Tang Design Interns created patterns inspired by the Museum’s exhibition and event history.