Granite countertops come in many different colors. The fusion of different rocks, minerals, and ores gives granite a unique color that is hard to duplicate. No two granite pieces have exactly the same shade, giving each granite countertop a touch of uniqueness and individuality.
Naturally occurring granite is either gray, black, or beige. While granite is usually composed of silicate bases, which are clear or milky in color, their base colors are derived from other materials. In its molten form, granite is a superheated mixture of different materials, including minerals from the earth's core. As the mixture hardens, these minerals melt and exude a dark natural dye, staining the rock as it forms.
Black and gray granite generally have high carbon content, with the gray variety also containing fused quartzite. The beige variety is usually a combination of quartz and sandstone. These materials have been fused under immense heat and temperature, staining the silicate base with the naturally reddish tint of sand.
Selective homeowners may find these colors too drab, so engineered granite has become available. Materials other than quartz and carbon are used to color the basic stone. This has led to the availability of red, blue and even purple granite countertops. Red granite usually has melted iron mixed into the silicate magma base, while melted beryl chloride is commonly used to create the blue variety. Purple granite is commonly a combination of these, but other manufacturers prefer to use phosphates to create the purple coloring. Phosphates create a stone that is closer to pink or violet than the deeper hues created by combined beryl and iron.
Graining and detailing
The graining and web-like designs present in granite are created by traces of other materials in the granite magma. Depending on their concentration, these materials can add highlights and detail to a granite magma base, altering its character and texture. Modern technology now allows manufacturers to control the webbing and line patterns in a granite slab by introducing molten material into the mixture at specific stages of the formation.
Adding drops of iron to a magma base while the magma is still hot will create a structure of red lines and veins. To create this effect, the magma must be cooled rapidly after the iron has been allowed to disperse. This freezes the iron in place prevents it from accumulating in a specific spot. On the other hand, introducing droplets of smoked quartz crystal while the magma is already in its cooling phase will create milky white highlights on the surface.
Perhaps the most attractive details in granite samples are created by amber, a stone from tree sap calcified and hardened over millions of years. Depending on when the amber is introduced into the silicate magma, bits of orange crystal or a web of orange lines can be created in the granite. However, amber can be expensive, and amber highlights can dramatically raise granite prices.