Introduction: Mineral Benches: Gold

This is a project conceived for the Market Street Prototyping Festival in San Francisco, April 2015.
Creators include Sabrina Habel, FICTILIS and fabricator Mary Anne Kluth


San Francisco first boomed in population because of the Gold Rush, when nearby gold mineral deposits were found in 1848 in Coloma, California. Now a tech-boomtown, fueled by neighboring Silicon Valley, much of San Francisco’s population rely on the minerals embedded in digital devices (tin, tantalum, tungsten, and gold, among others). Both gold and digital tech devices are status items contributing the rumor of fantastic riches long associated with the dream many people share when moving to San Francisco.

Mineral Benches: A California History is a series exploring the industrial uses and historical relevance of minerals that have shaped San Francisco. Crystalline-formed sculptural benches and chairs will accurately depict the minerals they represent (e.g. a gold nugget, a silvery piece of tantalum, a heavy chunk of tungsten, the brilliant blue of California’s gemstone Benitoite, etc.), playfully many times larger than actual ore specimens.

A QR coded information-portal will be on each piece identifying the mineral it represents, common uses of the mineral, and a story or facts about how that mineral consumption relates to the San Francisco Bay Area. The person encountering the benches will have a place to rest while learning about the mineral’s geological basics, mining practices, industrial applications and the social and environmental implications of the minerals experienced locally. Mineral Benches: A California History creates a surreal landscape on Market Street, making a space for people to meet, relax, take photos and learn.

Step 1: Materials

  • Magic Sculpt (sold in 2 or 10 gallon tubs) Need around 3 gallons per bench, depending on final size and elaborateness
  • Fiber glass
  • Primer paint(gold or white/interference, various colors) at least 6 gallons
  • Resin
  • Loose metallic pigments
  • Respirator with particulate matter filters around
  • Cardboard
  • Foam/ chicken wire - to support fiber glass
  • Gaff tape or duct tape
  • Lumber- pine 2 x 4s and boards for bench
  • Brackets and screws (90 degree joints for bench reinforcement)
  • Box of nitrile/latex gloves
  • Good quality hand sander and coarse sand paper
  • Good scissors for cardboard
  • Table saw
  • Good quality drill
  • Shop vacuum for sanding Magic Sculpt
  • Sandbag (optional for weighting the bench down)

Step 2: Design

We consulted artist Mary Anne Kluth, who works in the art department of a local theme park, to design our prototype. She has ample experience making faux rocks and boulders.

From the photos you can see the design she sketched for our gold nugget bench, including top view and cross section and detailed exterior. The nugget itself is based upon a real gold nugget recently discovered in Butte County, California. It is the largest nugget discovered in California since the Gold Rush of the 1800s which we chose since it reinforced the current relevance of the mineral to the San Francisco region.

The design had to be light weight enough to be portable but sturdy enough to hold the weight of people sitting on it. The final design is composed of the strategic placement of a wooden armature and covered in fiber glass. Should we continue the project to include more types of mineral benches, we would modify this design by Mary Anne to fit each structure in the series.

For the information portal we researched the mineral gold in historical, industrial, economic, technological and contemporary contexts. We synthesized information (with clickable links to our online research) in a simple, easy to explore format and uploaded to our website to host the information for our QR code.

Step 3: Fabrication

  • Safety first! Make sure to use respirator and gloves when handling dangerous materials.
  • Cut wood to desired shape based on your design.
  • Assemble wood pieces and attach bottom wood supports to create a stable 'bench' using brackets and screws
  • Follow directions of Magic Sculpt and along with cardboard, foam, and chicken wire create the volume and topography of the bench
  • Once Magic Sculpt has thoroughly set, sand down rough or undesired shapes
  • Follow directions for fiber glass* and drape/encase entire volume with fiber glass, make sure places meant to be sat on are reinforced by wood - fiber glass alone will not hold the load. Create fiberglass 'shelf' in the inner cavity of the bench if you wish to use a sand bag to weigh down the bench.
  • Sand rough edges and add/subtract to the bench as needed until the shape you desire is created
  • Cover with primer and paint base color
  • Mix resin with pigment and paint metallic resin over surface, repeat as necessary until appropriate color and luster is achieved
  • Affix sign/placard with QR code on bench. We used Google Docs to compile our information portal and uploaded it to our website. Free QR code generators are available online. In the photo we tried to paint on our QR code but use caution with this approach, the surface must be flat and fairly smooth in texture. In the end we printed the QR code and mounted it in a plastic holder affixed to the bench.

*Be especially careful when handling fiber glass, if you have never used fiber glass before, please take the time to learn and experiment on small projects before attempting this. Wear appropriate clothing and protection.*

Step 4: Installation

From the map included in the photos, we intended our gold nugget to be close to a major bank within our Festival street section. We ended up placing our bench nearest to Chase Bank.

Our team used the bed of a pick-up truck to transport the bench. It should be carried by 2-3 people and we suggest covering your hands when touching raw edges of fiberglass. We tilted the bench to install a sandbag to keep the bench weighted down and stationary. We gave the QR code a final test to make sure it was working properly.

Step 5: Interaction

Our project was straight forward in that we wanted you to see our golden nugget larger than life, perhaps sit on it, and scan the QR code if your curiosity was piqued. No guidance or on-site instruction required.

Included are photos taken by the public and some shared on Instagram!