Welcome to my EarthCache!
An EarthCache is a special type of geocache where there is no container to find. Instead, you explore a unique geological feature and answer questions to claim your find, along with posting a photo. This EarthCache is part of the Kitchener Rock Walk, which explores geological features within downtown Kitchener. These EarthCaches are designed to be completed on foot, allowing you to explore the downtown core while observing the different stone types used in local buildings and monuments.
This EarthCache focuses on the mica-rich Barre granite, often marketed as “Rock of Ages” granite, used at the Kitchener War Memorial. While granite is commonly known for its strength and durability, this location provides an excellent opportunity to closely examine mica, one of granite’s key minerals, and understand how its presence affects the rock’s appearance, structure, and performance as a building stone.
Access Notes
This EarthCache is located at a public monument and can be completed entirely from sidewalks and publicly accessible areas. Please be respectful of the memorial and its surroundings. Do not climb on the structure or disturb any commemorative elements. No scratching, chalking, or collecting is permitted; all observations must be visual only.
EARTHCACHE REQUIREMENTS
To log this EarthCache, you must visit the site and complete all logging tasks listed below. Your answers must be based on your own observations made at the location. Logs that do not adequately address the questions or that are missing the required photograph may be deleted.
Logging Questions
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Can you see flakes or shiny surfaces of mica with the naked eye? If yes, describe their colour and shape.
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Are the mica grains evenly scattered throughout the granite, or do they appear clustered in certain areas?
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What does this suggest about how the minerals crystallized?
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Compare the mica you see to the other visible minerals. Do the mica grains appear flat and sheet-like, or blocky like quartz and feldspar?
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Mandatory: Post a photo of yourself or a personal item (such as a GPS or signature item) with the Kitchener War Memorial visible in the photo. The photo does not need to show your face but must be unique to you.
Geology Lesson: Mica in Barre (“Rock of Ages”) Granite
Rock of Ages granite is quarried primarily from the Barre region of Vermont, an area internationally known for producing high-quality monument stone. While all true granites contain quartz, feldspar, and mica, Barre granite is notable for its relatively visible mica content, which contributes to its distinctive speckled appearance and subtle sparkle when viewed in sunlight.
Mica is a group of silicate minerals that includes biotite (dark mica) and muscovite (light mica). In Barre granite, mica is most commonly seen as biotite, appearing as black or dark brown flakes. Unlike quartz and feldspar, which form blocky, interlocking crystals, mica grows in thin, flat sheets. These sheets reflect light easily, making mica one of the easiest granite minerals to identify with the naked eye.
At this site, mica can often be recognized by its shiny, platy surfaces and its tendency to form thin flakes rather than chunky crystals. Even when the flakes are small, their reflective nature causes them to stand out against the lighter feldspar and glassy quartz. This visual contrast is a key identifying feature of mica-rich Barre granite.
Granite forms deep within the Earth’s crust when molten magma cools very slowly over long periods of time. As the magma cools, different minerals crystallize at different temperatures. Feldspar and quartz form much of the rock’s rigid framework, while mica crystallizes into flat sheets within the spaces between other minerals. The slow cooling allows these mica sheets to grow large enough to be seen without magnification.
The presence of mica plays an important role in granite’s behavior as a building stone. While mica is softer than quartz and feldspar, its sheet-like structure helps relieve internal stress during cooling and later during temperature changes at the surface. In carefully balanced amounts, mica contributes to granite’s overall stability without significantly weakening it. Barre granite contains enough mica to be visually distinctive, but not so much that the rock becomes prone to splitting.
This balance is one reason Barre granite has been so widely used for monuments and memorials. It can be precisely cut and polished, yet remains strong and resistant to weathering. The visible mica also adds subtle texture and depth to carved surfaces, enhancing legibility and visual interest over time.
Unlike metamorphic rocks such as schist, where mica becomes strongly aligned and causes the rock to split easily, mica in granite remains randomly oriented. This random orientation preserves granite’s massive strength and prevents it from breaking along flat planes. The lack of mineral alignment confirms that Barre granite is an igneous rock that has not been altered by later metamorphism.
At the Kitchener War Memorial, the mica-bearing Barre granite connects deep Earth processes with human history. By observing the mica flakes within this stone, you are seeing minerals that crystallized millions of years ago, now serving as a durable and symbolic material chosen to commemorate memory, sacrifice, and permanence in the urban landscape.
AI Content Disclosure: Some of the descriptive text was created with assistance from AI tools. All information has been reviewed and verified by the cache owner for accuracy.
This cache was placed by a PROUD Platinum EarthCache Master.
