There is an endless bounty of eye-catching gemstones throughout the world and this spectacular boulder opal is one unique beauty that looks like a shimmering crystal encased in a tree fossil. Its opalescent sheen seeps through the cracks of the seemingly wooden rings in lustrous hues of emerald green and aqua blue. Like something out of a fairy tale, the triangular piece radiates through an organic pattern mimicking the growth rings of tree.

The mineral pyrite, or iron pyrite, also known as fool's gold, is an iron sulfide with the formula FeS2. This mineral's metallic luster and pale brass-yellow hue give it a superficial resemblance to gold, hence the well-known nickname of fool's gold. The color has also led to the nicknames brass, brazzle, and Brazil, primarily used to refer to pyrite found in coal.
In crystallography, the cubic (or isometric) crystal system is a crystal system where the unit cell is in the shape of a cube. This is one of the most common and simplest shapes found in crystals and minerals.

Bride Duangreuthai Amnuayweroj and groom Kasemsak Jiranantiporn fly while attached to cables during a wedding ceremony ahead of Valentine's Day at a resort in Ratchaburi province, Thailand, February 13, 2016. Four Thai couples took part in the wedding ceremony arranged by the resort. (Photo by Athit Perawongmetha/Reuters)

Cardi B performs at the “Night Two At Palms Casino Resort's KAOS Dayclub & Nightclub With Cardi B, G-Eazy, J Balvin For Grand Opening Weekend” event on April 6, 2019 in Las Vegas, Nevada. (Photo by Roger Kisby/Getty Images for Palms Casino Resort)

A person dressed as a zombie mermaid poses for a photo as she interacts with patrons at the Haunted Hotel Takeover Halloween party at hotel Ziggy in West Hollywood, California, U.S., October 29, 2022. (Photo by Mario Anzuoni/Reuters)

A person practices ski-joering at the Avoriaz resort in the French Alps on February 11, 2021. (Photo by Jeff Pachoud/AFP Photo)

Couples (L-R) Chaiyut Phuangphoeksuk and Prontathourn Pronnapatthun, and Nichapatr Koomsombut and Pirat Rungthongoran run from sheep during their wedding ceremony at a resort in Ratchaburi province February 13, 2015. Three Thai couples took part in the wedding ceremony arranged by a resort themed around fun activities ahead of Valentine's Day. (Photo by Athit Perawongmetha/Reuters)

Models wait for their turn at an audition for the upcoming Lakme Fashion Week (LFW) Summer/Resort 2017 in Mumbai, India, 14 December 2016. Around 83 national and international models participated in the audition from which five got selected. The LFW Summer/Resort 2017 is scheduled to start from 01 to 05 February 2017. (Photo by Divyakant Solanki/EPA)