Yooperlites

Since we bought a black light and stayed in Grand Marais we made the kids go out at night to look for Yooperlites.   This is what I found on a quick google search.  

Yooperlite is the name Rintamaki came up with, but the rocks are actually Syenite rocks that are rich in fluorescent Sodalite. The discovery was published in Mineral News in 2018. ... The glowing rocks can be found mostly on Lake Superior between Whitefish Point an Grand Marais, and on the Keweenaw Peninsula.

The kids lasted about 30 minutes, except for Darby who was up for the adventure.  She eventually did get cold which was probably good because I am pretty sure Brad would have been out there until the next morning.  

The next morning Darby and Bo were on the beach and a guy showed them what agates looked like.  

This is a picture from the shop of what a Yooperlite rock looks like under the black light.