Agate to Opal: Gems of the Northwest

OMSI has been a hands-on science museum from the beginning, but it may surprise some people that we also feature collections! In fact OMSI houses over 30,000 pieces including natural history, ethnographic and historical objects. We also partner with other museums and institutions to bring their collections to the public.

Right now, curious visitors will find a small but diverse collection of minerals from the Rice Northwest Museum of Rocks and Minerals on display in the Planetarium Hallway. Every jasper, opal or garnet you see was found in Oregon, or in a neighboring northwest state or province (some specimens are from British Columbia).

Agate forms in volcanic rocks, and typically appears transluscent with brightly colored bands of fine-grained minerals. This transluscent quality is whats sets it apart from Jasper.

As a carbonate mineral, calcite will dissolve in acid. This unique property is the reason the powdered form of Calcite is often found in health products like vitamins. 

Epidote forms in other minerals, most often Marble. A high iron content will give it a dark green color, but Epidote is most often found in a shade of pistachio green.
The rare Meta-autinite appears flourescent green. The mineral's high uranium content makes it valueable but also dangerous as a potentially radioactive material. Handle with care! 

Hydrated sodium and aluminum create the mineral Natrolite, which is known for its long, slender crystal structures.

Opal forms at low temperatures in many different types of rock throughout the natural world. It has a significantly high water content for a mineral - almost a quarter.

Pyrite is a common iron sulfide. This mineral's characteristic metallic hue led to it's nickname of "Fool's Gold". You may have collected this one as a kid.

A common and abundant mineral, Quartz has been used throughout history in the making of jewelry and gemstones.
Thundereggs may look like ordinary rocks on the outside, but contain minerals like agate, jasper, or opal in their centers. Oregon has the higest concentration of naturally occuring thundereggs in the United States!

Want to see more? Amateur geologists and other fans can visit Rice Museum in Hilsboro to view an extensive collection of rocks, minerals, and gemstones. OMSI will also be hosting our annual Agate & Mineral Show on Friday, February 8th in the auditorium. 

Add New Comment



Search form