Most granite used for countertops is polished to a high-gloss finish giving it a mirror-like appearance. On closer inspection however, many granites have certain natural characteristics such as “pitting”, “fissures” or “dull spots” that may at first cause some concern. It is important to understand the geological reasons for these characteristics to fully appreciate the beauty of stone.
A characteristic referred to as “pitting” is normally due to the fact that granite is a natural product that has a crystalline structure, sometimes resulting in small spaces between the varying mineral crystals. In some cases, certain tiny crystals may also be removed during the polishing process, causing the pits to become more visible. Various steps are taken during the finishing process to reduce the visibility of these pits, but they cannot be totally avoided in all granite types. Pitting will not become worse with regular use or with the passage of time.
Many types of granite have small “fissures” or hairline cracks on the surface of the slab, usually more visible in the larger quartz crystals. These surface fissures should not be confused with structural cracks that permeate the entire slab. Fissures are a natural result of the heating and cooling of the stone during its formation millions of years ago. Fissures will not grow or expand over time.
The final appearance of the polished surface of each type of granite is determined by the specific composition or “mix” of quartz, feldspars and other minerals. While the overall appearance will be that of a high-gloss finish, some components within the granite may not accept the same level of polish as the rest of the crystals, which can result in "dull spots" or "watermarks." Often these spots are visible on the darker crystals present in some granites. The hardness, composition and any other characteristics are taken into account during the polishing process and all efforts are made to achieve the highest level of gloss possible for each specific material.
While the type and specific composition determines the amount of pits, fissures and dull spots, some granites exhibit these characteristics more than others, and they may also be more or less visible depending on the lighting conditions present in a room. Lighting plays an important part in the overall appearance of a finished granite countertop surface.
Pits, fissures and dull spots do not compromise the integrity of the stone in any way; they are natural characteristics of stone and will not impair the function or durability of the material. They are an expression of nature and add to the allure of the stone, which sets it apart from man-made surfaces.