Today's Gem Quiz: What Do Sunstones and Bon Ami Cleanser Have in Common?

Here's a fun quiz. What do this beautiful sunstone from the Smithsonian National Gem Collection and Bon Ami's original formula cleanser have in common?

The answer is feldspar.

Sunstone — along with moonstone, amazonite and labradorite — are the members of the feldspar family most familiar to the jewelry-buying public. The mineral in its common form makes up about 60% of the Earth's crust, but on rare occasions the mineral presents crystals that shimmer like the rainbow on a soap bubble.

Sunstones exhibit a reddish to golden "schiller," resulting from light reflecting off numerous tiny copper or hematite (iron oxide) flakes scattered within the stones. The golden sheen flashing off of the Tanzania-sourced 17.91-carat sunstone, above, is due to the presence of hematite platelet inclusions.

More often than not, however, common feldspar has been considered a worthless byproduct of pegmatite mining. Pegmatite consists primarily of the minerals quartz, mica and feldspar. At a mining site in Connecticut during the 1820s miners diligently captured the quartz and mica and discarded the feldspar. And that's the way it was for the next 60 years.

But then in 1885, J.T. Robertson noticed that the shovels used by the miners to separate the feldspar from the other materials were always so bright and shiny. Robertson realized that the relatively soft feldspar (6.0 on the Mohs scale) was doing a great job of polishing the shovels and could be mixed with soap to produce a non-abrasive cleanser. By 1886, Robertson would be harvesting the feldspar "waste" at the quarry to produce Bon Ami soap cleaners, which were billed as the best way to clean windows, floors, oilcloth, woodwork, tin, brass, copper, nickel and glassware.

The product was a runaway hit, as it replaced the harsher, quartz-based scouring products on the market at the time. The Husband Quarry in South Glastonbury, CT, became the primary source of feldspar for the Bon Ami Company.

The company introduced the logo of a newly hatched chick and the slogan, “Hasn’t Scratched Yet!” The phrase, which is one of the US's oldest registered trademarks, referred to the fact that baby chicks live off the nutrients of its egg for three days before having to scratch the ground for food.

On its website, Bon Ami noted that today’s city dwellers no longer make this barnyard connection between non-scratching Bon Ami and non-scratching chicks, but the chick remains a popular mascot.

"We wanted to show that, despite our mineral ingredients and powdered form, Bon Ami is still a gentle cleaner and won’t scratch countertops or fine hard surfaces," the company stated.

Despite aggressive competition from post-WWII products, such as Zud, Ajax and Comet, Bon Ami has remained true to its roots.

"Over the years, there has been pressure for Bon Ami to adapt to the marketplace with new additives and artificial fragrances to compete with mainstream cleaning products," the company wrote. "When more and more chemical cleaning products were introduced in the 1970s, Bon Ami began receiving letters from consumers who thanked us for NOT adding chlorine bleach, perfume and dye."

Today, consumers are very sensitive about keeping harsh chemical cleaning products out of their homes, and Bon Ami is making a comeback by promoting itself as an environmentally friendly, "green" product — thanks to feldspar.

Credits: Sunstone photo by Greg Polley / Smithsonian. Bon Ami product shot and 1909 print ad via bonami.com.