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

Paraguay is home to beautiful azurite, amethyst, white sandstone and volcanic rocks like basalt and marble. Most significant deposits of these beautiful rocks are found along the Paraguay river.

There have been stunning amethyst geodes uncovered in Paraguay and these are some of the most exciting finds for collectors.

Types of Rocks in Paraguay

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.

Azurite

Azurite is a stunning deep blue copper containing mineral that usually results from the weathering of copper ore.

Azurite is relatively soft with a hardness of 3.5 to 4 meaning that it can be scratched easily.

Azurite is easy to identify by its bright to deep blue color, but it can be further confirmed by an acid test. Azurite does effervesce when exposed to hydrochloric acid.

Paraguay has several copper deposits that are presently being mined and azurite is found in conjunction with these deposits.

It has been found in Encarnation, Paraguay along with the present copper deposits.

White Sandstone

Sandstone is a relatively soft stone made of individual grains of sand that have cemented together into a sedimentary stone.

White sandstone is a type of sandstone that is made of individual grains of white sand. The grains of sand are made of quartz and feldspar.

The white layers of the Caacupe series of stones at Tobati, Paraguay are striking white sandstone.

Red Sandstone

There are also some large red sandstone deposits created by the same process in the Aregua neighborhood in Paraguay.

The sandstone here has an unusual structure.

The quartz in the sandstone has caused these sandstone pieces to form long crystal like pieces.

They are called columnar joints because the long colloms of sandstone are all piled nicely together like a very satisfying tetris game.

These large pieces of red sandstone have been peeled apart into what looks like large crystals.

Limestone

Limestone is primarily made of calcium and many of the cliffs that surround the Paraguay River. Limestone can weather quickly.

Limestone is generally light white to gray, but the stone can be other colors if it contains a lot of organic material.

Limestone is relatively soft and can easily be scratched with a knife.

The individual grains of calcium in the limestone can be very small or larger and can often contain fossils of shells or other marine life. Look for smooth areas, holes or depressions to investigate for fossils.

Limestone is most often created on the ocean floor. The animals that live in the ocean often create calcium rich skeletons and shells that remain on the ocean floor and break down into small calcium pieces.

These calcium pieces compress together to form limestone.

Limestone is then often lifted from the ocean floor through tectonic movement or volcanic activity.

Marble

Along the banks of the Paraguay river from Rio Apa to Concepcion the steep cliffs are made of limestone and marble.

Marble is formed when limestone is exposed to heat and metamorphosed as has occurred in these rock formations.

The marble and limestone weather at different speeds and in different conditions giving these incredibly steep cliffs a layered appearance.

While polished marble used for building and carving is generally very light in color, weathered marble may appear gray.

The white marbles chosen for sculpture result from exceptionally rare and pure limestone.

Basalt

Another volcanic rock in Paraguay is Basalt. This dark gray to black rock is found in Fox De Iguazu.

Basalt forms when lava is pushed to the surface and cools. This makes it an extrusive rock.

Basalt is generally very dense and often contains crystals that have formed during the creation of the stone.

Basalt is often the casing for the incredible amethyst geodes commonly found here and in Uruguay.

Basalt is a very common rock on Earth and if you have a dark gray or black stone with a small grained dense texture it is likely basalt.

Lighter colored dense stones may also be andesite, but the two stones are very difficult to distinguish in the field.

Granite

Granite is a coarse grained rock that forms when magma cools slowly close to the surface of the Earth.

Granite is a relatively dense stone that has a variety of colors. The stone breaks fairly irregularly, so the pieces may look like brightly colored driveway gravel.

Granite can come in a variety of colors and the variation of color is one of the defining characteristics of the stone. Granite comes from the word grain as the stone has the appearance of many grains of stone pressed together.

Granite can range in color from deep black, red, browns, greens, yellows to beiges and tans.

The rocks often contain mica pieces that create a glittering appearance when polished.

Granite is exported from Paraguay for use as a building stone and decorative uses like countertops.

Amethyst

Amethyst is a deep purple quartz type often used in jewelry. Amethyst creates trigonal crystal clusters that are characteristic of quartz.

The crystals are often found embedded in basalt to form geodes. These may be overlooked as just round gray rocks, but be sure to check for any signs of crystals that may be hiding inside.

Amethyst found in Paraguay is not as high quality as those found in nearby Uruguay, but they are plentiful in the basalt floods there.

Amethyst is graded based on color, the deeper the purple the more valuable the stone.

Rocks in Paraguay

Paraguay is a good place to find interesting rocks as most of the interesting geology is along the Paraguay River.

You can book boat tours of this area and it can allow you to see much of the diverse geology of the country.

Be sure to only collect rocks where you have been given permission.

Obey any posted rules or regulations and local laws. Collecting and removing natural materials from protected areas can result in fines or customs issues.

Conservation efforts in Paraguay are focused on protecting forest habitats of native wildlife, so expect some strict regulations in forested areas.

If you are looking for specific minerals in Paraguay consider supporting the local economy and purchasing local stones from local venders.