Types of Rocks Found in Chile: A Guide to the 7 Most Common You’ll Spot

Chile contains some of the most amazing stones in South America

In this article, you’ll learn more about the geology of Chile.

Types of Rocks Found in Chile: A Guide

Disclaimer

The information provided in this article by YesDirt.com is for informational purposes and is subject to change. Laws are updated. Accessibility guidelines and restrictions change. Be sure to confirm the land status and collection rules before you travel to an unfamiliar location or collect any material.

Introduction

Chile is a beautiful country with a varied geology.

Northern Chile is home to sprays of atacamite, gypsum, and chrysocolla.

Alluvium, Proustite and many types of quartz are also found in Chile.  

Chile is a very long country that covers many geological zones.

A north to south trip through Chile will bring you many rock hunting and geological observing opportunities. 

The geology of Chile is often divided into three major zones, the Andes, the central valley and the costal range.

Each area has its own geological factors and commonly found specimens. 

Beside the major zones Chile is one of the most tectonically active areas in the world as the country contains the edges of 5 plates and they are subducting and colliding constantly.

This results in frequent earthquakes including the largest ever recorded. 

Central Chile is home to the largest mineral museum in South America where you can find alluvium and more than 2,000 mineral samples.   

Proustites

Proustite also known as ruby silver ore is a sulfur and metal containing mineral that forms prismatic crystals that are silver to red. 

It looks like ruby dipped in liquid silver. 

The crystals often have a “dog-tooth” appearance and terminate in rhombohedral crystals.

Proustite has a hardness of just 2 to 2.5 and the most notable specimens have been found in Chanarcillo in Chile. 

Atacamite

Atacamite was first described in the Atacama Desert in Chile in 1801.

This dark green halide mineral contains copper and chloride. 

It can be found on oxidized copper deposits and is often found with cuprite. 

It has been found in areas of volcanic heating of water, known as fumaroles. 

In Chile this metallic stone can be seen in the Farola Mine where some notable specimens have been found. 

Atacamite can look like copper patina. It has been found in the patina of the Statue of Liberty, this is known as synthetic Atacamite.  

The dazzling sprays of the mineral are very desirable and collectable as Atacamite is relatively rare. 

Gypsum

The Atacama desert also has produced some very beautiful specimens of Gypsum.

Gypsum is a relatively soft stone with a light gray to white appearance. 

Gypsum is mined for industrial application as it is a component in chalk, drywall, and plaster.

Very white gypsum, called alabaster, is also used in decorative applications. 

Many large beautiful examples of gypsum have been discovered in the Atacama region of Chili.

The specimens are light to dark gray and they may have a crystal like structure. 

Gypsum is soft and relatively water soluble.

Dehydrated gypsum is often called plaster of paris, a white powder that can be rehydrated and molded. 

It has a hardness of 2 and can be scratched with the tip of a knife. 

Chrysocolla

Chrysocolla is a copper silicate stone with a striking bright blue appearance.

It is often uncovered in areas where there is a large copper deposit. 

It can be difficult to identify as the silica content can vary widely.

The hardness can vary from 2 to 7 depending on the mineral composition.

The darker colors tend to be softer and not suitable for polishing and jewelry making. 

The stone has a similar appearance to turquoise and is sometimes used in the same ways in silversmithing and jewelry making. 

Orbicular Granite

Orbicular granite is a volcanic stone that has distinct concentric dark circles regularly distributed throughout the stone. 

Orbicular granite has a striking appearance and a fine grained texture.

This unique formation of granite is thought to be the result of nucleation during the formation of the granite. 

Nucleation is the rapid chemical reaction when two substances react. 

Orbicular granite deposits are usually very small, but in Chile they are very large.

There are three main large examples and they are in protected areas. 

  • About 11 kilometers North of Caldera 
  • Cordon de Lila
  • Ciera Recoba, Chaiton  

These deposits are all very large and stunning.

They are notable to geologists, but most of the orbicular granite that is known to be found in Finland. 

Inquire about specimens for sale at La Recova. 

The Mineral Museum

The Museo Mineralogico (as it is called in Spanish) is located in Copiapo and holds the largest collection of rocks and minerals in South America. 

This museum is incredible, but not well known by tourists. 

The museum is a great place to see the large collection of over 14,000 specimens from Chile and around the world. 

It was built around the silver mining operation in Copiapo that used to support the economy in the area. 

The museum operates in partnership with the University of Atacama.

The university took over the museum which was established by the Copiapo Mining College in the mid 19th century. 

The museum has been in existence for 150 years.  

The museum is organized by crystal structure and at the time of writing there is no entrance fee. 

The best way to find up to date information on this museum is through the Museo Mineralogico Facebook Page. 

Rocks in Chile

When collecting rocks in Chile it is best to go with an experienced local guide.

Many rock and mineral enthusiasts visit Northern Chile where mining is more active. 

Some of the mines in the region have public areas where tourists can view the mining operations.

The best way to experience all Chile has to offer is to find a reputable local guide to help you gain access to these tours. 

Mining operations in Chile focus on copper.

Chile is the largest exporter of copper in the world making copper containing stones like chrysocolla more plentiful. 

Chile also exports about 5% of the gold in the western hemisphere, and almost half of that gold is a byproduct of the extensive copper mining.

There are 41 National Parks in Chile and they each have strick rules about collecting and removing natural material, so be sure to obey any posted signage or local laws. 

Types of Rocks Found in Chile