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14 November 2023

Geology Word of the Week: Q is for Quartzite

def. Quartzite: A metamorphic rock that consists primarily of interlocking grains of the mineral quartz. Quartzite forms when quartz-rich sandstone undergoes metamorphism.   The term “quartzite” is an example of a geologic term that can be a little confusing. Most of the time, geologists use the term “quartzite” to refer to a metamorphic rock, which is the definition that I have provided above. Sometimes, geologists also use the term “quartzite” …


7 November 2023

Geology Word of the Week: P is for Pahoehoe

def. Pahoehoe: A type of lava with a smooth or undulating surface. Pahoehoe lava flows often resemble coils of rope and are most commonly found in basalt. Pahoehoe is Hawaiian word that is pronounced “pah-hoy-hoy”.   Pahoehoe is a term used to describe a lava flow that has a smooth or undulating surface. Many pahoehoe flows resemble coils of rope or, in some cases, messy piles of rope. Pahoehoe is …


30 October 2023

Geology Word of the Week: O is for Outcrop

I attempted to revive the Geology Word of the Week earlier this year, but a few busy projects at work and also writing my first book derailed my plans. Let’s try again! I have a Geology Alphabet to finish. I’ll use some photos from my trip to Scotland earlier this year to illustrate this post. Without further ado, here’s the next word…   def. Outcrop: An exposure of rock formation …


15 January 2023

Geology Word of the Week: L is for Luster

def. Luster (or Lustre if you use British spelling): The way in which the surface of a mineral or rock interacts with light. Words used by geologists to describe luster include metallic, sub-metallic, dull (or earthy), vitreous, waxy, silky, greasy, pearly, and adamantine.   Luster is a physical property that is used by geologists to help identify minerals and rocks. Other physical properties that geologists use for identification are hardness, …