Vesicular Basalt (Lava Rock)
Basalt (Igneous Volcanic Rock) · Mineral Specimen / Industrial Mineral / Decorative Stone
Crystal System
Amorphous/Aphanitic; primarily composed of microscopic crystals with occasional macroscopic phenocrysts (Cubic/Monoclinic/Orthorhombic micro-structure)
Mineral Group
Silicates (Mafic Silicate Rock)
Chemical Formula
Complex mixture: ~45-52% SiO2 with high MgO, FeO, and CaO contents
Formation Process
Igneous (Extrusive); forms from the rapid cooling of magnesium-rich and iron-rich lava at the Earth's surface
About This Crystal
A dark, fine-grained volcanic rock containing numerous small cavities (vesicles) formed by trapped gas bubbles during solidification. Appearance is rough, matte, and highly porous.
Physical Characteristics
Color: Charcoal gray to black with reddish-brown oxidation; Streak: Gray; Cleavage: None; Fracture: Uneven/Conchoidal; Gravity: 2.8–3.0; Fluorescence: None
Optical Properties
Opaque; Non-refractive in bulk; sub-vitreous to dull luster depending on mineral content; no significant optical phenomena like labradorescence in this specimen
Hardness & Durability
Origin Region
Globally distributed; primary sources include Iceland, Hawaii (USA), Italy, and the Deccan Traps (India)
Hardness & Durability
Mohs Hardness: 5–6; High toughness due to interlocking grain structure; very stable and resistant to most environmental factors
Care & Maintenance
Wash with warm soapy water to remove dust from pores; avoid harsh acids which can react with minor carbonate inclusions; mechanically durable and light-stable
Rarity & Value
Very Common; low monetary value as a single specimen; valued primarily for landscaping, construction, and ornamental use
Special Characteristics
Vesicular texture (pitted surface); may contain micro-crystalline olivine, pyroxene, or plagioclase feldspar; highly porous and lightweight compared to non-vesicular rocks
Lore & History
Historically used for grindstones and building materials; in folklore, it is considered a stone of grounding and strength representing the element of fire and earth's core energy.