Skip to content
Earth Know
  • Order Articles
  • Refund Policy
  • Blog
    • Environment
    • Geology

Rocks

Poikilitic texture with augite surrounding plagioclase
Home » Geology » Rocks

What Is Poikilitic Texture and How Does It Form?

The poikilitic texture is an igneous rock texture in which large mineral crystals engulf or completely enclose many smaller ones

Categories Rocks
an ophitic ilmenite gabbro rock
Home » Geology » Rocks

Ophitic and Subophitic Textures

While learning about igneous rocks, you often come across the terms ophitic and subophitic textures or fabrics. What do they

Categories Rocks
Example of pegmatites - Tourmaline varieties and calcite crystals
Home » Geology » Rocks

Pegmatites Rock Characteristics and Formation

Pegmatites are intrusive or plutonic rocks with unusually large mineral crystals. Typical grains are > 1cm (0.4 inches). Some are

Categories Rocks
What are gabbroic rocks
Home » Geology » Rocks

Gabbroic Rocks and Gabbro Varieties

Gabbroic rocks or gabbroids are coarse-grained, dark-colored mafic rocks. A mafic rock is one rich in iron and magnesium. These

Categories Rocks
Basalt rock types or varieties - Olivine basalt
Home » Geology » Rocks

Basalt Rock Types and Varieties

There are several basalt rock types and varieties you should know. However, before going to the time, not everyone knows

Categories Rocks
Andesite and Basalt rocks images
Home » Geology » Rocks

How Does Andesite and Basalt Differ

Both andesite and basalt are fine-grained, volcanic, or extrusive igneous rocks. Volcanic or extrusive rocks form on the Earth’s surface.

Categories Rocks
Gabbro is a coarse-grained, dark-colored mafic rock
Home » Geology » Rocks

Gabbro Texture, Composition and Uses

Gabbro is a dense, coarse-grained, dark-colored mafic rock. It is mostly a plutonic rock but can also be extrusive/subsurface. Mafic

Categories Rocks
Diabase, Dolerite or microgabbro - A medium-grained, dark-colored mafic rock
Home » Geology » Rocks

Diabase or Dolerite Properties and Composition  

Dolerite, diabase, or formally microgabbro, is a dark-colored, medium-grained subvolcanic rock equivalent to basalt or gabbro in composition. Subvolcanic or

Categories Rocks
Basalt rock color, texture and appearance
Home » Geology » Rocks

Basalt Properties, Composition and Formation

Basalt is a mafic or dark-colored, volcanic or extrusive igneous rock. Mafic refers to rocks high in dark-colored minerals rich

Categories Rocks
How thundereggs or thunder eggs look like. A sample from- Baker Ranch, New Mexico
Home » Geology » Rocks

What Are Thundereggs (Thunder Eggs) and Where to Find Them?

Thundereggs or thunder eggs are nearly spherical structures or rocky bodies filled with mineral masses or crystals in rhyolite volcanic

Categories Rocks
Older posts
Newer posts
← Previous Page1 … Page4 Page5 Page6 Next →
  • About Us
  • Terms of Use
  • Delivery Policy
  • Refund Policy
  • Privacy Policy
  • Contact Us
  • Cookie Policy
  • Disclaimer
© 2025 EARTH KNOW. All Rights Reserved
Next Page »