On The Run #30 - A Place To Rest

Welcome to the 'On the Run' series, brought to you by Troopbiz and DOBIEST! Whether you're squeezing in a quick cache between errands, out for a leisurely Sunday stroll, or tackling your long run, these easy-to-find hides are perfect for filling in your map and adding a little adventure to your day. We hope this series gives you just the excuse you need to get outside and get some

This is an Earthcache. There is no physical container at the posted coordinates, but rather a geological lesson for you to explore. Please review the information on the cache page, then make your way to Ground Zero to make your observations and answer the two questions below. Email your answers to the cache owner by clicking the "message this owner" button above, and once complete, you can log this cache.

Thanks and happy caching!

QUESTIONS

1. What minerals create the shiny, reflective flecks in the granite shown at GZ?  

2. Is there any blue tint evident in the granite, if so, what do you think caused this?  

(Optional) Post a picture of yourself with the bench in the background.

What is Blue Pearl Granite?

Blue Pearl granite is an igneous rock known for its striking appearance, characterized by reflective blue and silvery flecks within a dark background. This unique look comes from its mineral composition, particularly the presence of feldspar crystals. These feldspar crystals contain tiny inclusions that reflect light, giving the stone its signature iridescence. The reflective quality is enhanced by the way light interacts with the crystal surfaces, creating a shimmering effect that makes Blue Pearl granite a popular choice for decorative purposes.  

The formation of Blue Pearl granite begins deep within the Earth's crust. It forms as magma slowly cools and solidifies over millions of years, allowing large mineral crystals to develop. The mix of dark and light colors in the rock is due to its mineral components: darker areas are often formed by minerals like biotite or amphibole, while lighter regions are dominated by feldspar and quartz. This slow cooling process is typical of intrusive igneous rocks, which solidify beneath the Earth's surface.  

One of the most striking features of Blue Pearl granite is its blue tint, which is primarily caused by feldspar. The feldspar in this granite contains light-reflecting inclusions of other minerals or even internal microstructures that scatter light in a way that creates a blue hue. The intensity of the blue color can vary depending on the angle of light and the specific mineral composition of the stone. This unique optical effect, known as "schiller" or labradorescence, is highly prized in natural stone.  

The Blue Pearl you'll see at GZ was quarried in Norway, where it is found in large deposits. The rock is part of the Larvikite family, named after the town of Larvik in Norway. Its durability and resistance to weathering make it ideal for both indoor and outdoor applications, including countertops, flooring, and monuments. The unique geology of the region, with its tectonic activity and specific cooling conditions, has contributed to the formation of this exceptional granite.