Types of Rocks on St. Vincent and Grenadines: A Guide to the 7 Most Common You’ll Spot

St. Vincent and the Grenadines contain some of the most amazing stones in the Caribbean.

In this article, you’ll learn more about the geology of St. Vincent and the Grenadines.

Types of Rocks on St. Vincent and Grenadines: A Guide to the 7 Most Common You’ll Spot

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.

The island of St. Vincent and the Grenadines are a collection of volcanic islands with very recent volcanic activity. There are examples of white sand beaches and volcanic black sand beaches.

The composition of the more than 30 islands that make up the Grenadines is very similar. Most of the islands are uninhabited, but nine are inhabited and open to visit.

There are many interesting geological sites to visit on St. Vincent and the Grenadines. The Japer Tunnel and Mt. Soufriere trail are accessible to tourists and give access to very interesting geology.

Limestone

Limestone is a light yellow to gray fine grained stone that is relatively soft. It is easily weathered by wind and water and limestone forms cliffs and other rounded stone formations.

Limestone forms when calcium in marine life like coral, mollusks and crustaceans die and their shells and skeletons break down in the ocean.

The limestone on St. Vincent and Grenadines is mostly composed of the remains of coral reef.

The reef ecosystem around the Grenadines is the healthiest reef ecosystem in the world. You can visit these reef systems in Tobago Cay.

This area in the south of the Grenadines is the area that is the focus of the conservation efforts of the reef.

Pillow Lava

Pillow lava is lava that extrudes underwater and the lava hardens and floats to the surface because of the trapped gasses within the lava.

Lava is under tremendous pressure while it is under the crust of the Earth and when it is released it expands and forms porous rock.

These pillow lavas float to the surface and join together into pillow lava formations. It is possible to make out individual pillow lavas within a grouping.

Pillow lavas can be seen on Baradal within the Tobago Cay. These are best viewed from a boat with a local guide.

Andesite

Andesite is a volcanic rock that is formed when lava is pushed to the surface and hardens. The composition of the lava determines the type of rock that is formed.

Andesite forms from a higher viscosity lava that is similar in viscosity to peanut butter.

Andesite is a lighter colored fine grained stone that often has incorporated gems and stones.

Andesite can be found on Bequia is often a hornblende or inosilicate. These rocks have a hardness of 5-6 and are generally dark in color.

Hornblende andesite has a varied appearance and may look like a rock with embedded long crystals.

Basalt

Basalt is another type of volcanic rock that is formed when lava erupts or extrudes to the surface.

Basalt is generally dark in color and the basalt found in Grenadines and St. Vincent often contains olivine.

Olivine and garnets can sometimes be found embedded in basalt. These semi precious stones are often found after careful rock breaking.

Basalt can be found on Bequia, the second largest of the Grenadines.

Rock Art

Rock art is visible in many areas in the Caribbean, but the rock art or petroglyphs found on St. Vincent and Grenadines is extensive and large.

The petroglyphs are found on andesite boulders inside cave structures.

The petroglyphs found on St. Vincent are consistent with those found in South America with some rayed faces only found on St. Vincent.

The largest petroglyphs are found in Buccament where the largest petroglyphs in the Lesser Antilles are seen in a rock shelter.

The rock art is 8 meters long and it is a script like engraving that is written twice. The design includes dots, circles and loops. There is some speculation that this is an early form of writing.

The rock art speaks to the importance of rock to the earliest humans on Earth. Early inhabitants of these islands used the rock for record keeping and we have the benefit of having this record preserved in stone.

Black Point Tunnel or Jasper Tunnel

On St. Vincent you can visit the Black Point Heritage and Recreational Park and see the incredible tunnel that was constructed by the British using slave labor.

The tunnel is made of basalt and was constructed to make transportation of sugar easier.

The tunnel is an incredible sight and it can be visited with a guide. The location of the tunnel and the park also gives you access to the black sand beaches.

The volcanic rock that formed this area has broken down into very dark black sand. The sand does get hot, so be sure to wear appropriate shoes.

The park is very accessible and has many facilities like gazebos and restrooms.

White Sand

Many of the beaches on the Grenadines boast sparkling white sand. The white sand beaches are inviting and beautiful.

The white sand is a result of the breaking down of limestone.

On the Grenadines this limestone is mostly formed from coral reef remains as the healthy reef ecosystem moved through phases of growth.

Buccament Bay is a great area to visit if you are looking to see large volcanic boulders and strikingly white sand.

Much of St. Vincent and Grenadines is protected as a National Park. The National Parks, Rivers and Beaches Authority controls these areas and collecting sand and shells is prohibited in protected areas.

Princess Margaret Beach is considered one of the most beautiful white sand beaches on St. Vincent and Grenadines.

Rocks on St. Vincent and Grenadines

Conservation efforts on St. Vincent and the Grenadines have been largely successful as they have worked to help preserve endangered species on the island.

The islands have not been heavily visited by tourists as it did not have an international airport until 2017.

The extensive National Park system has preserved much of the natural beauty of the island making them stunning places to visit.

When visiting be sure to obey any posted rules or regulations concerning collecting and removing any sand shells or stones. Be sure to declare any items you are taking through customs as well.

The Grenadines is also a hub for boating and yachting. There are many opportunities for diving and experiencing underwater caves and shipwrecks.