One of many different forms of Rhyolite, the Mushroom variety is a wonderful stone that any rockhound or geology buff would love to hunt down – and it can be polished up into a beautiful specimen.
This article will help you to understand exactly what this igneous marvel is and how you might go about finding a piece of your own.
Below, you can learn how to differentiate Mushroom Rhyolite from other rocks and minerals, what key features to look out for, and what similar stones to avoid.
What is Mushroom Rhyolite?
Mushroom Rhyolite is a special combination stone, also known as Rainforest Jasper, that forms from lava flow with high silica content.
It is an igneous rock that is similar to basalt, but it is harder when it cools, and the lava flow itself is more viscous.
Rhyolite cools and solidifies very quickly when it comes into contact with the surface.
There are a lot of nodules and pockets of crystals that form in Mushroom Rhyolite because the high concentration of the stone allows it to trap gas as it solidifies, which can then fill with a solution.
The distinctive bubbles in Mushroom Rhyolite are known as thundereggs and they can form in layers that build up over time, resulting in overlapping spherical shapes.
Rhyolite comes in many different forms, one of the most well-known of which is pumice that is a useful exfoliator because it is full of tiny holes.
Mushroom Rhyolite is a denser formation than pumice, and it is a combination stone because it occurs when the holes in Rhyolite are filled with grey Perlite.
Where Can I Find Mushroom Rhyolite?
Mushroom Rhyolite can be found in many areas that have had volcanic activity in the past, but it is mainly sourced around Phoenix in Arizona.
Specific types of Rhyolite are given different names when they are found in different geographic regions.
Mountain Rhyolite, for example, is found in south-western New Mexico and Balaklala Rhyolite is from the Klamath Mountain area of California.
It is not uncommon to find large deposits of Mushroom Rhyolite on the surface of the Arizona desert, and it can be very easy to hunt down and sift through to spot the most interesting patterns and formations.
How Can I Identify Mushroom Rhyolite?
This particular form of Rhyolite is prised for its speckled or spotted appearance.
Mushroom Rhyolite is a green matrix with distinctive bubbles of grey, outlined in red, which have an appearance similar to mushrooms when the stone is cut.
The grey bubbles should overlap, with a halo of red on much of the outer layers.
Though there are variations of the shapes and shades that you will find with this particular rock, it is the blooms of grey that are easiest to identify, so that is what to look out for first.
It is easy enough to spot by looking for the patterns on the outside of larger stones, though they are much more distinctive on clean edges.
The mushroom effect is what you are looking for, but the layers can be close together or further apart depending on how were formed.
When it comes to color, the greys can be less noticeable depending on the shades in the rock around them.
Sometimes the reds can be quite dull, but they can also have a bright orange hue that is very striking, and there are various shades of green that they may be set into as well.
What Might You Mistake for Mushroom Rhyolite?
Mushroom Rhyolite can be distinguished from the other, more common, forms of Rhyolite because it contains such a strong pattern.
Rhyolite can also contain many other gem deposits, because it allows gas to be trapped inside cavities in the stone, but Mushroom Rhyolite has cavities that have been filled with grey Perlite rather than colored gems or crystals.
Red jasper, jaspillite, and heliotrope (commonly known as bloodstone) are other forms of Rhyolitic lava that can be mistaken for Mushroom Rhyolite.
These can be distinguished due to the lack of grey bubbles within them, and the distinctive red coloring that is much stronger in these stones.
Mushroom Rhyolite is also known as Rainforest Jasper, because of the green coloration and intricate details in the stone.
Sometimes, rounded calcite formations can be mistaken for Mushroom Rhyolite because of their bulbous appearance, but the bubbles in Mushroom Rhyolite are grey, smooth and set into the face of the stone.
What is Mushroom Rhyolite Used For?
Rhyolite on the whole is rarely used in construction or manufacturing.
It is easy to fracture, and, despite its strength, it is often vuggy.
Mushroom Rhyolite can contain many small pockets of air and little cavities that have not been filled, so it is likely to crack and fracture under pressure.
It is more often used to make jewelry or crushed stone than for tools.
While some ancient weapons and stone tools have been found that were made from Rhyolite, it is very rare for the Mushroom variety to have been used, as its appeal is more aesthetic than practical.
What Sort of Properties Do People Associate with Mushroom Rhyolite?
Rhyolite in general, and Mushroom Rhyolite in particular, is thought to be associated with the earth and building connections with the planet and its inhabitants.
People appreciate this particular stone because its vibrant colors and intricate patterns are said to resonate with joy and happiness, so some view it to be beneficial for confidence and self-esteem.
For those that believe in the metaphysical properties found in geology, the green colour that can be found in Rhyolite is indicative of healing, particularly in the past.
Mushroom Rhyolite is also seen by some as a protective stone that can give feelings of strength and support.
What Makes Mushroom Rhyolite Special?
Mushroom Rhyolite is a special type of igneous rock, and a beautiful variant of Rhyolite, particularly because of the wide variety of patterns and formations that you can find.
It is not too tricky to get your hands on some, and seeking out the perfect piece can be really rewarding.
For those that appreciate the wonders of geology, every rock is a unique marvel, and Mushroom Rhyolite is no exception.
It tells a visual story of its own formation and the shapes that bloom within it can almost look like they are alive.
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