Iron Rock Hill in Cumberland, RI and the mountain of Taberg in Småland, Sweden are ancient formations of a rare eruptive rock with shared properties. Shared Magma celebrates the intersection of Late Proterozoic geology and a contemporary friendship between Swedish artist Kajsa G. Eriksson and Robin Wheelwright Ness, Senior Library Technologist in Digital Preservation at the John Hay Library. Featuring original works created from iron-based pigments by Eriksson, Shared Magma explores how deep time, shared lifetimes, and the future entangle. This digital collection is in development, with additional images to be added in time. Uncanny and synchronistic events took place in the Spring of 2023. Kajsa was exploring a mountain called Taberg in Småland, Sweden when she encountered a sign that read "Taberg Mountain was formed 1.2 billion years ago and consists of titanomagnetitolivinit, an unusual rock found only here and in Rhode Island, USA." Kajsa texted Robin about this unlikely connection between the ancient geology of Sweden and that of Rhode Island, two places also joined by their forty-year friendship. Attaching images of the bluish, dark grey rock speckled with feldspar crystals, Robin explained that Cumberlandite is the Rhode Island rock the label refers to, often thought only to exist on a 3.75-acre plot of land in Cumberland. The next day, Robin was out mudlarking—searching for lost or discarded items that tell a story of the past—along the Blackstone River, when she spotted something grey and speckled. She held a refrigerator magnet close, and it stuck. This was Cumberlandite, a beautifully water-polished example of the ancient rock. Deep time and the Earth had given Robin and Kajsa a magnetic, magmatic connection…a gift. The land now known as Rhode Island once abutted another land mass with a volcanic arc running between them. This microcontinent, known as Avalonia, would later collide with and become a part of the continent Gondwana, and later still, Pangea. In Avalonia, about 1.2 billion years ago, a rare and complex rock was born from intense heating and cooling. The rock was composed of dozens of minerals and heavy with iron. When Cumberland-born religious leader Adin Ballou came across it in the early 19th century, he imagined that “some unaccountable volcanic freak, in the remote past, must have thrown it up from the depths below.” Around 1.2 billion years ago, in what is today the middle of southern Sweden, there was a weakness in the bedrock running north to south. The area was geologically active, and during an intense eruptive event, magma forced its way up through a deep fissure and then cooled. The rock had undergone similar extreme heating and cooling as that of the magmatic event in Avalonia. Coincidentally, it contained the same rare mineral composition…one found nowhere else on earth. At the time of these two geologic events, only soft-bodied, multicellular creatures pulsed through the oceans. Eons passed, dinosaurs came and went, enormous sheets of ice descended and receded, and humans began inhabiting pockets of the globe. Two formations of rare ironstone, one in the northeast corner of Rhode Island and the other in Småland, Sweden, have stood through it all. Taberg, or Berget, is simply translated as “The Mountain.” During excavations in 1976, archaeologists discovered slag heaps rich in iron made from bog ore and red soil and dating from at least the end of the 10th century. For hundreds of years, local peasantry worked the ore, which was well regarded for its quality. When shipments of it arrived in France, medieval pistol smiths exclaimed, “C'est fer de Takaberg!" (“It's iron from Taberg!”) Forced labor at the mountain is first evidenced in Jönköping’s Register from 1480-93, when a woman was sentenced to serve the mountain for her crime of theft. Additional examples of penal servitude at Taberg follow. In 1618, Sweden’s “War King,” Gustav II Adolf, visited the mountain and decreed it to be the country’s southernmost mining district. He chose sites suitable for blast-furnaces and forges and drew skilled workers to Taberg by offering them land and tax breaks. If the local farmers did not become miners, they were evicted from their properties. As King Adolf conducted military campaigns in an effort to expand Swedish territory, the British were colonizing land across the Atlantic Ocean. New England, and Rhode Island, were soon on the map. In 1690, “Forty Acres of Shruffy (wild and untamed) meadow and swampy land, near unto a rock called Iron Rock” were purchased by English settler James Ballou and gifted to his son Obadiah. Heavy rocks from the hill were useful in “fastening” horses and as ship ballast. Mining of Iron Mine Hill started in 1703, when the ore was smelted by Philip Brown at a furnace named Abbott's Run in Cumberland to construct cannons, tools, and weapons. In the 1730s, at least three additional furnaces were built nearby; Unity Furnace, Furnace Carolina (under license from King George II), and the Crabtree. As one of the only sources of iron in the area, the geological formation was important in Rhode Island’s early iron production processes. Analysis of iron ores from archaeological digs conducted by Krysta Ryzewski, Ph.D, Brown 2008, on the Greene family farm in Warwick, revealed that ore from Iron Mine Hill was forged there to create tools. Iron was produced at the Greene farm from 1733 to 1781, with enslaved and itinerant Indigenous and African laborers part of the operations. In 1984, the land of Iron Mine Hill was in private ownership and increasingly surrounded by suburban development. At the same time, Taberg’s future was under debate. Turning the mountain into a ski resort, opening it up to vanadium mining, and protecting it under Sweden’s Nature Conservation Act were all under consideration. Fifty miles to the west of Taberg, in the textile factory town of Borås, a cross-cultural friendship was burgeoning. Bonding over the dark, alternative, post-punk sounds of Bauhaus, the Cure, Killing Joke, and the Swedish band Cortex, the magnetism of sisterhood grew from a place of cultural alienation. Alternative 80s culture was an anti-establishment response to a society encouraging individuals to reach for the stars. Kajsa and Robin were simultaneously part of the booming, capitalist culture, and at the same time against it. The bubblegum colors and big blond hair didn't match the feelings of dread, loneliness, and boredom that existed for them, and is evidenced in their correspondence archive. They were drawn to art that delved into pain, anguish, and self expression. They moved through the world like spiders or bats, compelled to dark places, creeping in corners, hiding, looking for alternative places to hang out…ruins of stone buildings, graveyards, and in small music clubs underground. In 1986, the Swedish Society for Nature Conservation bought all the shares in Taberg’s mining company, and the mountain began its life as a protected nature reserve. The alkaline mineral content of Taberg’s soil supports 400 types of plants and ferns and six endangered types of mosses. The biological diversity of the mountain so impressed Swedish biologist Carl von Linné when he visited Taberg in 1741 that he described it as “Smålands mirakel”—the miracle of Småland. People visit Taberg to hike its trails, take in the view from the top, tour the mine, learn its history, and visit the Bat Museum. The mountain is very important to the local community and is the site of many public events. In 2001, the town of Cumberland purchased Iron Mine Hill. The same year, at the foot of the hill, Tiffany & Company’s 100,000 square-foot jewelry manufacturing plant opened. The proposed Elder Ballou Road Local Historic District includes the Cumberlandite site, along with ruins of mining operations, remnants of the narrow gauge rail bed system, two graveyards, historical stone walls, and over forty acres of conservation land with diverse wooded wetland.