Crater Rock Museum

07/04/2026

Wishing everyone a spectacular (and safe) 4th of July. 🎆🇺🇲🎇

And in case you need a break from the heat today, WE'RE OPEN.

05/14/2026

03/31/2026

We're on the lookout for eggs 👀

*Update and REMINDER*
April 2nd eggs are being hidden and the picture clues are in the comments! Some are out already and a few more will be hidden later!
***Make sure the drop down says "most recent comments" when looking for today's clues***

REMINDER-This is for children only please. Adults please do not go to the park to pick these up. Let the kiddos have fun finding them.

FDairy Queen Grill & Chilln. WeCrater Rock Museumation hints in this comment thread.

Coming this Monday!! Thank you Dairy Queen Grill & Chill and Crater Rock Museum for sponsoring some prizes 🐰🐰

03/17/2026

We missed due to the chaos of the Gem Show but here's a familiar friend with a hidden talent.

Fluorite - CaF2

Found worldwide, this unassuming combination of Calcium and Fluorine is used in a variety of industrial processes. It creates flux which cleans impurities from steel and aluminum smelting, making metals stronger and easier to work with. It creates sharp image lenses for telescopes, microscopes, and cameras. It's also the primary source of hydrofluoric acid, which is used in creating refrigerants, plastics, and high-octane gasoline.

Ironic that the mineral used so heavily in purifying is hiding it's own 'dirty' secret.

Fluorite comes in just about any color you can imagine, but not all can be seen with the naked eye. Pure fluorite is colorless but impurities (usually rare-earth elements) make it come to life under ultra-violet light. In fact, the phenomenon of fluorescence - when light is re-emitted after being absorbed as energy inside a substance- is named for this mineral.

If you own a piece of fluorite, test it out. Shine a UV light on it (short wave is best) or expose it to sunlight- it may show you a new side of itself. Then come check out the fluorescent display in the museum for even more color.

PS- Mention the mineral in this post for $1 off your admission fee until March 31.

03/13/2026

https://youtu.be/lt9CkmZSjhk?si=BigPGFlC3HNrPjBS

For more, visit https://kobi5.com

03/03/2026

It's that time of year again!

Come join us for our 2026 Roxy Ann Gem & Mineral Show. We have many vendors from the region, amazing specimens and jewelry, lapidary demos, mineral auctions,...

02/08/2026

It's almost Valentine's Day so this we're featuring a rose-colored treat.

RHODOCHROSITE - MnCO3
Found in hydrothermal vents alongside precious ores like silver, lead, & copper, this mineral comes in many forms including delicate rosettes, large stalactites and the iconic white and pink banded veins which give it the nickname "bacon stone".

While it does looks scrumptious and at a 3.5 on the hardness scale it *might* be soft enough to chew, we'd advise against- One of it's main components, Manganese, is toxic if inhaled.

This piece is currently on display at the Tucson Gem & Mineral Show in the Main Exhibition space but we have plenty of others including the iconic Alma Mater on permanent display in Frieda Hall.

PS- Mention the mineral in this post for $1 off your entrance fee until March 1. :)

02/04/2026

NEW ARRIVAL ALERT!

These delicate pieces survived a fall from a 1,500 foot lava fountain then travelled 2,500 miles so you could be some of the first people in the continental US to see them!

RETICULITE from the Episode 41 eruption at Halemaʻumaʻu Crater of Mount Kiluaea.

Reticulite is an extremely lightweight, highly vesicular volcanic rock composed of over 95-98% air, making it the least dense rock on Earth! Sometimes called "thread-lace scoria," it's actually a rare variety of pumice which forms from rapidly cooled, high-fountain basaltic lava where bubble walls burst and fuse into a delicate, interconnected lattice.

These pieces are from the recent 'Episode 41' eruption where hundreds of people, including our favorite geologist, were caught in a hail of raining ash and tephra for nearly 8 hours.

This rare material in now on display in the Delmar Smith Gallery. Come see it for yourself!