A Complete Guide to Rhyolite: A Common Light-colored Volcanic Rock
Rhyolite is a highly silicic, fine-grained, light-colored volcanic or extrusive igneous rock. It is a felsic rock with mainly quartz, alkali feldspar, plagioclase, and minor
Rocks
Pumice: A Frothy, Light-Colored Volcanic Rock with Many Uses
Pumice is a very low-density, form-like, mostly light-colored glassy volcanic rock with a vesicular texture, not a mineral. This rough, porous rock forms from mostly
Understanding Scoria: A Highly Vesiculated Dark-Colored Volcanic Rock
Scoria is a mafic to intermediate highly vesiculated dark gray, black, reddish, or brown extrusive igneous rock (volcanic glass). This vesicular textured pyroclastic rock forms
What Are Apache Tears or Obsidian Balls?
Apache tears (marekanite or obsidianites) are smoky, dark gray, gray-brown, or black indented tear-shaped, rounded, or subangular small obsidian balls, pebbles, or nodules measuring up
What Are Pele’s Tears and How Do They Form?
Pele’s tears are small jet-black teardrop, obovoid, spherical, or cylindrical-shaped volcanic glass droplets formed when tiny blobs of ejected magma cool quickly. They often precede
How Do the Mystical Pele’s Hair Form?
Pele’s hair is a formal geological term that volcanologists give to the golden-brown, fiber or thread-like strands of volcanic glass formed naturally from blowing out
What Is Lithology and What Does It Entail?
Lithology studies physical properties like color, texture, composition, or grain size of visible rock outcrop units, core, or hand samples, including with a low magnification
What Are Lapilli Tuffs and Lapillistones
Lapilli tuff and lapillistone refer to a pyroclastic rock formed from predominantly lapilli-sized (2-64 mm) pyroclasts ejected during an explosive volcanic eruption. These rocks can
Get Insight on What Lapilli Are and Their Types
Lapilli are rock fragments or pyroclasts measuring 2 to 64 mm (0.08 to 2.52 inches) in diameter formed and ejected during an explosive eruption. These