Fire 🔥 & Stone 🪨 EarthCache

Located in Wurtland, Kentucky, is the Greenup County War Memorialto honor local heroes. One of the  features of the memorial is the granite statue of a firefighter and child. This EarthCache focuses on the geology of the granite used in this statue, why this stone was chosen, how its properties help it endure Kentucky’s climate, and how to identify the type of finish applied to it.

Geology of the Granite

Granite is a durable igneous rock composed mainly of quartz, feldspar, and mica. These interlocking mineral crystals give granite its speckled appearance and make it highly resistant to scratching, weathering, and erosion.

Granite is commonly used in monuments because:

• It withstands freeze, thaw cycles, preventing cracks in cold winters.
• It resists rain, wind, and chemical weathering more effectively than softer stones.
• Its density helps maintain sharp edges and smooth surfaces over long periods.

Kentucky’s climate, humid summers, cold winters, and frequent precipitation, makes granite a reliable choice for long-lasting memorial art.

Types of Granite Finishes

    1.    Polished: A polished finish creates a glossy, reflective surface that enhances the natural color and pattern of the granite. This is achieved by grinding and buffing the surface with fine abrasives. Polished finishes are often used for memorials and monuments because they highlight the stone’s natural beauty and make inscriptions more visible.
    2.    Honed: A honed finish is smooth but matte. The surface is ground to a consistent flat finish without polishing, giving the granite a softer appearance. Honed finishes are less slippery than polished ones and are often used for flooring and countertops.
    3.    Flamed: A flamed finish is rough and textured, created by exposing the granite surface to high heat, which causes the crystals to pop and creates a slightly uneven surface. This finish is ideal for outdoor use because it provides a slip-resistant texture and a more rugged appearance.
    4.    Bush Hammered: A bush hammered finish is very rough and textured, created by repeatedly hitting the granite with a specialized hammer that creates small, uniform indentations on the surface. This finish creates a highly textured surface, often used for architectural elements and outdoor walkways.

How to Identify the Type of Granite Finishes

Granite finishes affect both the texture and appearance of the stone. By closely examining the surface and using touch and light reflection, you can determine which finish was used. Here’s how to test and identify the most common finishes:

1. Polished Finish
    •    Look: A polished finish will have a high-gloss, mirror-like surface. Colors and patterns in the granite will appear vibrant and well-defined.
    •    Touch: The surface will feel completely smooth and slick.
    •    Test: Reflect light from a phone flashlight or the sun onto the surface. If you see a clear reflection of the light, it’s likely polished.

2. Honed Finish
    •    Look: A honed finish will have a smooth but matte or satin appearance. The colors will appear more muted compared to a polished surface.
    •    Touch: The surface will feel smooth but without the slippery feel of a polished finish.
    •    Test: Shine a light on the surface. If the reflection is soft and diffused rather than sharp, it’s likely honed.

3. Flamed Finish
    •    Look: A flamed finish will have a rough, uneven surface with small pits and a slightly lighter color due to the heat treatment.
    •    Touch: It will feel rough and gritty under your fingers.
    •    Test: Run your hand across the surface. If it feels textured and you notice small, irregular pits, it’s likely flamed.

4. Bush Hammered Finish
    •    Look: A bush hammered finish will have a very uniform, textured appearance with small indentations across the surface.
    •    Touch: It will feel rough and bumpy.
    •    Test: If the texture is consistent and feels like small dots or dimples, it’s likely bush hammered.

How to Identify the Type of Granite Finishes

    1.    Start by examining the surface of the memorial under natural light.
    2.    Use the touch test, run your hand gently across different sections of the memorial.
    3.    Test for reflectiveness by shining light on the surface.
    4.    Compare different parts of the memorial,  inscriptions are often polished for clarity, while bases or sides might have a honed or flamed finish for contrast and durability.