Quartzite
Quartzite is a non-foliated metamorphic rock formed from sandstone, characterized by its exceptional hardness, durability, and crystalline appearance, making it a premium choice for countertops, flooring, and exterior applications where both aesthetics and performance are priorities.
Composition
Quartzite is a metamorphic rock formed when pure quartz sandstone is subjected to intense heat and pressure within the Earth's crust. This metamorphic process transforms the individual quartz grains, fusing them together into an interlocking mosaic of quartz crystals. The primary mineral component is quartz (silicon dioxide, SiO₂), typically comprising over 90% of the stone, with minor amounts of other minerals such as mica, iron oxides, and feldspar that contribute to its color variations and veining patterns. Quartzite's metamorphic formation results in a stone that is significantly harder, denser, and less porous than its parent sandstone. The material typically has a density of 2.65-2.75 g/cm³, a hardness of 7 on the Mohs scale (the same as quartz itself), and very low porosity (typically 0.1-0.6%), contributing to its exceptional durability and resistance to staining, scratching, and etching.
Properties
Hardness
7 on Mohs scale
Quartzite's exceptional hardness, equivalent to that of quartz itself, makes it highly resistant to scratching and abrasion. This property places it among the hardest natural stones used in building applications, surpassing granite (6-6.5) and significantly harder than marble (3-4).
Density
2.65-2.75 g/cm³ (165-172 lbs/ft³)
Quartzite has a high density, contributing to its substantial weight and solid feel. This density provides excellent durability but requires adequate structural support, particularly for countertop and large-format applications.
Porosity
0.1-0.6%
Quartzite's exceptionally low porosity makes it naturally resistant to staining and water absorption. This property contributes to its excellent performance in wet environments and reduces maintenance requirements compared to more porous natural stones.
Acid Resistance
Excellent
Unlike marble and limestone, quartzite is highly resistant to etching from acidic substances such as lemon juice, vinegar, and wine. This property makes it particularly suitable for kitchen countertops and other surfaces exposed to acidic materials.
Heat Resistance
Very Good
Quartzite offers excellent resistance to heat damage, withstanding temperatures up to approximately 1200°F (650°C) before showing signs of thermal shock. This makes it suitable for applications near heat sources, though direct contact with very hot objects should still be avoided.
Color Range
Moderate (whites, grays, tans, pinks, blues, greens)
Quartzite occurs in a range of colors determined by mineral impurities present during its formation. While many quartzites are white or light-colored with subtle veining, varieties with significant mineral content can display dramatic patterns and colors ranging from gold and pink to blue and green.
Applications
Kitchen Countertops
Quartzite has emerged as a premium countertop material, prized for combining marble-like aesthetics with superior durability and performance. Its exceptional hardness (7 on Mohs scale) makes it highly resistant to scratching from knives and kitchen implements, while its low porosity and acid resistance prevent staining and etching from common kitchen substances including citrus, wine, and tomato products. Quartzite countertops are available in various finishes including polished (high gloss), honed (matte), and leathered (textured), each offering different aesthetic and functional characteristics. The material's natural heat resistance allows it to withstand brief contact with hot cookware, though trivets are still recommended. While generally requiring less maintenance than marble, quartzite countertops benefit from periodic sealing (typically annually) to maintain optimal stain resistance. Popular varieties include White Macaubas, Taj Mahal, Sea Pearl, and Azul Macaubas, each offering distinctive coloration and veining patterns.
Bathroom Vanities and Shower Surrounds
Quartzite's water resistance and durability make it an excellent choice for bathroom applications including vanity tops, shower walls, and tub surrounds. In these wet environments, the stone's low porosity prevents water absorption and associated issues such as staining and bacterial growth. For shower applications, quartzite can be installed as large-format panels that minimize grout lines or as smaller tiles in various patterns. The material's natural beauty creates spa-like environments, with varieties featuring subtle veining patterns reminiscent of marble but offering superior performance. Quartzite bathroom surfaces require less maintenance than more porous stones, though periodic sealing is still recommended. The material pairs well with various bathroom fixtures and finishes, from traditional to contemporary, offering design versatility despite its premium positioning.
Flooring
Quartzite flooring offers an exceptional combination of durability and natural beauty, suitable for both residential and commercial applications. Its hardness and wear resistance make it ideal for high-traffic areas, while its crystalline appearance creates sophisticated, light-reflective surfaces. Available in various formats including large-format tiles, standard square and rectangular tiles, and irregular flagstones, quartzite flooring can suit diverse design styles from contemporary to transitional. For interior applications, quartzite is commonly used in entryways, kitchens, living areas, and bathrooms, where its durability and water resistance are advantageous. Exterior quartzite flooring and pavers are suitable for patios, walkways, and pool decks, with textured finishes providing slip resistance. The material's thermal properties prevent it from becoming excessively hot in direct sunlight, making it comfortable for barefoot contact in outdoor applications.
Wall Cladding
Quartzite wall cladding creates dramatic interior and exterior surfaces with distinctive crystalline character and natural veining. For exterior applications, quartzite cladding offers excellent weather resistance, freeze-thaw durability, and color stability with minimal maintenance requirements. Installation methods include both traditional masonry techniques and contemporary rain screen systems with mechanical anchoring. Interior quartzite wall cladding adds sophistication and visual interest to residential and commercial spaces. Installation options range from large-format panels that showcase the stone's veining patterns to smaller tiles in various dimensions and arrangements. Quartzite's often light-colored background with contrasting veining creates striking feature walls that become focal points in interior design. Popular applications include feature walls in living areas, fireplace surrounds, and commercial spaces such as hotel lobbies and high-end retail environments.
Fireplace Surrounds
Quartzite fireplace surrounds create elegant, durable focal points for interior spaces. The material's natural heat resistance makes it well-suited for this application, while its often dramatic veining patterns and crystalline appearance add visual interest and sophistication. Quartzite can be used for simple mantel and surround combinations or for more dramatic floor-to-ceiling installations. The stone's hardness allows for precise cutting and finishing, enabling both traditional profiled edges and contemporary minimalist designs. Lighter quartzite varieties with gray or gold veining create marble-like fireplace surrounds with superior durability and resistance to smoke staining. The material pairs well with various interior styles from traditional to contemporary, with different finishes (polished, honed, or leathered) allowing further customization to suit specific design aesthetics.
Exterior Applications
Quartzite's exceptional durability and weather resistance make it suitable for various exterior applications including facade cladding, landscape features, and outdoor kitchen countertops. For exterior cladding, quartzite offers excellent freeze-thaw stability, UV resistance, and color fastness, maintaining its appearance with minimal maintenance even in harsh environments. The material's low water absorption rate prevents issues associated with moisture penetration, while its hardness resists physical damage and erosion. In landscape applications, quartzite is used for garden walls, water features, stepping stones, and decorative elements, where its crystalline appearance creates distinctive visual effects in natural light. For outdoor kitchens, quartzite countertops provide the ideal combination of aesthetic appeal and performance, withstanding weather exposure while resisting staining from outdoor cooking activities.
Advantages
- Exceptional hardness and scratch resistance, surpassing granite
- Excellent resistance to etching from acidic substances
- Low porosity provides natural stain resistance
- Heat resistant, withstanding brief contact with hot cookware
- Marble-like appearance with superior durability and performance
- UV stable, maintaining color consistency even with outdoor exposure
- Freeze-thaw resistant, suitable for exterior applications in cold climates
- Lower maintenance requirements than many natural stones
Limitations
- Premium price point, typically higher than granite and marble
- Limited availability of some exotic varieties
- Requires professional installation due to weight and hardness
- Can be brittle at edges and corners despite overall hardness
- Periodic sealing recommended despite low porosity
- Significant weight requires adequate structural support
- Difficult to repair if damaged due to its hardness
- Some varieties labeled as quartzite may actually be dolomitic marble or soft quartzite, requiring careful sourcing
Sustainability Profile
Quartzite has a moderate sustainability profile when evaluated across its full lifecycle. As a natural stone, quartzite is non-renewable, and its extraction has environmental impacts, though these vary significantly depending on quarrying methods and location. The processing of quartzite is energy-intensive due to its exceptional hardness, requiring substantial energy for cutting, polishing, and finishing. Transportation impacts can be significant due to quartzite's weight and the concentration of high-quality quartzite quarrying in specific regions (particularly Brazil, Norway, and the United States), often requiring long-distance shipping to reach global markets. However, quartzite's exceptional durability and longevity contribute significantly to its sustainability through reduced replacement frequency and associated resource use. The material is inert and does not emit VOCs or other harmful substances. At end of life, quartzite can be repurposed or crushed for use as aggregate. Look for suppliers certified by the Natural Stone Council's sustainability standards or those who follow responsible quarrying and fabrication practices with efficient water recycling systems and waste reduction strategies. Some quartzite suppliers are now implementing more sustainable extraction and processing methods, including water recycling, energy-efficient cutting technologies, and quarry rehabilitation programs.