:O Could we see your laumontite? I knew opals were kept in water sometimes I didn’t know others did too! Ty for all your rock facts
Oh man, let me show you my absolutely stunning specimen of laumontite!!
This piece is about six inches long, and was collected from the upper peninsula of Michigan, right off the beach of Lake Superior. (My uncle found it!) As you can probably guess by its pastel colors, it belongs to the zeolite group of minerals.
While it may not look like much from a distance, up close it's an incredibly pretty specimen. Here are some closeups!
Look at those crystals!! Many of these brittle crystals have been broken by weathering, but they still display a great example of laumontite's crystal habit! Bladed sprays with very distinct faces.
The salmon pink coloration of this laumontite specimen is unique to Lake Superior! I believe it's due to the level of iron in the area.
Some of the crystals are growing intertwined with what appears to be calcite. (Though it may also be another zeolite mineral!) That's the shiny white stuff. It's a cool contrast to have the dull, sort of pearly pink laumontite crystals right next to the shiny white calcite.
Laumontite is a mineral which forms underwater, and has water as part of its crystal structure. If allowed to dry out completely, laumontite's crystal structure will lose its water molecules and decay into a powder called leonhardite. As such, it's a stone that requires some careful curation if you want to add it to your rock collection.
While the best way to store this rock would have been in a sealed container of water, I wanted to display it on a shelf with the rest of my collection, so I tried something a little risky! I soaked this specimen in a bath of heavily diluted Aileen's Tacky Glue, which is a craft glue that dries invisible and watertight. After soaking, I gently painted on multiple layers of the same diluted glue mixture, careful not to damage the brittle crystals. The idea was to create a watertight seal that prevented the stone from drying out. It sounds pretty wild, but this method is actually a common tactic for rockhounds trying to preserve laumontite!
As you can see, it worked really well! Despite being displayed in the open air on my shelf, the crystals remain beautifully defined. A difficult rock to care for, but so incredibly worth it!
