What is volcanic "bread crust," and what makes it different from lava? One major difference is their appearance. Lava typically has a smooth and glossy surface due to its high temperature and flow rate, while volcanic bread crust has a rough and textured surface due to its slower cooling process. In fact, some types of volcanic bread crust can even resemble the texture of actual bread!

The most significant difference between the two is their chemical composition. Lava is primarily composed of molten silicate minerals, while volcanic bread crust contains a mix of minerals and fragments from previous eruptions. This can include pieces of other rocks, crystals, and even gas bubbles trapped within the solidified lava. Also another difference lies in their physical properties. Lava is extremely hot molten rock, ranging from 1,300 to 2,200 degrees Fahrenheit. On the other hand, volcanic bread crust has already cooled down and solidified on the surface.

Trindade Island, a small Brazilian island in the South Atlantic, is part of an impressive underwater volcanic chain called Vitória-Trindade. Located at 18°40’ in the Mid-Atlantic Ridge, this chain is the extension of the Trindade Victory Fracture Zone. The island itself is made up of five different volcanic episodes, each with unique lava flows and intrusions of silica rocks. These episodes are called the Trindade complex, Desejado sequence, Morro Vermelho Formation (MV), Valado Formation, and Vulcão do Paredão Formation. Over time, the volcanic spills have been covered by Holocene deposits, but they still stand as a remarkable part of the island's geological history.

Size of specimen: 80mm X 60mm X 35mm. This specimen ships with a Certificate of Authenticity, tag, tag stand, and information about volcanic bread crust and lava. Photo cube not included.

This "bread crust" would make a terrific addition to any geological collection that includes a study about volcanology.

This specimen ships with a Certificate of Authenticity, tag, tag stand, and information about volcanic bread crust and lava.