Molecule necklaces were featured on Buzzfeed and BUST magazine Geosmin Molecule Necklace in Silver. Petrichor is the term coined by Australian scientists in 1964 to describe the unique, earthy smell associated with rain. It is caused by the water from the rain, along with certain compounds like ozone, geosmin, and plant oils. Purchase includes a molecule information card, a natural jewelry box, and gift packaging. Gift? Add-on a hummingbird card for only $7: Art, Vintage, Chemistry, Bijoux, Molecule Necklace, Biology Jewelry, Science Jewelry, Compounds, Chemistry Jewelry