Quartz countertops have become increasingly popular in kitchens and bathrooms thanks to their durability, aesthetics, and low maintenance. But what exactly are these lustrous countertops made of? Here’s a deep dive into the composition and manufacturing of quartz countertops.
Composition of Quartz Countertops
The key ingredient in quartz countertops is, unsurprisingly, quartz. Quartz is a mineral that makes up 12% of the earth’s crust. It’s incredibly abundant in nature and therefore a relatively affordable material. Here’s what a typical quartz countertop contains:
- Quartz – Around 90% of a quartz countertop is ground quartz aggregate. Quartz provides hardness, rigidity, and resistance to scratches.
- Resins – Epoxy resins make up around 10% of a quartz countertop. Resins act as a binding agent to hold the quartz together. Polyester resins also contribute to stiffness and durability.
- Pigments – Pigments are added to resins to achieve the desired color and pattern. Popular colors for quartz countertops include whites, grays, browns, and blacks.
- Other Additives – Small amounts of other additives are used to enhance certain qualities. For example, recycled glass or shells may be included for sparkle and shine.
So in summary, quartz countertops are an engineered composite of natural quartz aggregates held together by polymer resin binders and pigments. The exact proportions and additives vary between quartz brands and colors.
Manufacturing Process
Quartz goes through an interesting manufacturing journey before becoming a kitchen countertop. Here are the key steps:
1. Sourcing and Crushing Quartz
Pure quartz slabs are mined from quarries across the globe. Quartz deposits are abundant in nature, so sourcing is not usually an issue. The mined quartz is then crushed into small granules and fragments to produce quartz aggregates.
2. Mixing with Resins and Pigments
The crushed quartz granules are mixed by hand or machine with liquid polymer resins and powdered pigments. The goal is to achieve a homogeneous material with a desired color and pattern. More pigment equals more vibrant colors.
3. Molding into Slabs
The quartz resin mixture is poured into molds and compacted under vibration and vacuum pressure. This compacting removes air pockets and allows thicker slabs to be molded, typically 1.2 to 2 inches thick.
4. Curing in Ovens
The pressed slabs are cured at 150-220°F in large ovens or autoclaves. Curing hardens the resins to produce a durable, stiff slab. Curing can take 15 minutes to over an hour depending on oven temperature.
5. Finishing and Polishing
Finally, the cured slabs are sanded and polished to achieve a smooth, glassy finish. Diamond abrasive pads and polishing discs are used to hone the surface. This brings out the sparkle and depth of color.
6. Inspecting and Packaging
Finished slabs are visually inspected for any defects, then packaged and shipped to fabricators or retailers. Slab sizes vary but are typically 30 square feet and 120 pounds.
So in summary, quartz countertops are made by blending quartz aggregates with resins, molding into slabs, curing in ovens, and finishing with polishing. The result is an engineered stone that’s highly durable for kitchens.
Why Quartz Makes an Excellent Countertop Material
The composition and manufacturing process of quartz produces a material with many desirable characteristics as a countertop:
- Hardness – Quartz is very hard and scratch resistant, allowing it to withstand heavy use in kitchens. Diamond is the only mineral harder than quartz.
- Stain resistance – Cured quartz resins create a non-porous surface that resists stains from spills and liquids. Sealing is generally not required.
- Heat resistance – Quartz can tolerate brief exposures to heat up to 300°F. Hot pans can be placed directly on the surface.
- Durability – Properly installed quartz is unlikely to chip or crack under normal use. The bound quartz makes the material highly resilient.
- Low maintenance – Quartz requires very little maintenance besides cleaning with soap and water. Annual sealing may help improve stain resistance.
- Aesthetic options – Diverse colors, patterns, and finishes are possible by varying quartz grades, resins, and pigments.
So if you’re looking for a low-maintenance, stylish, and durable surface, quartz is an excellent choice thanks to its uniquely engineered composition. Just be sure to enlist skilled professionals for proper installation. With the right fabrication and care, a quartz countertop can look pristine for decades.
Frequently Asked Questions about Quartz Countertops
Here are answers to some common questions about quartz countertops:
What are the differences between quartz and natural stone countertops?
Quartz countertops are engineered from crushed quartz while natural stones like granite or marble are cut directly from quarries. Quartz is non-porous while natural stones are porous. Quartz also has more consistent colors and patterns versus the unique veining in stones.
How do you clean quartz countertops?
For routine cleaning, wipe quartz down with a soft sponge or cloth and mild soap and water. Avoid abrasive cleaners or pads that could dull the surface. Blot up spills quickly before they can stain. More stubborn stains may require a non-abrasive cleaner designed for quartz.
Can you cut on quartz countertops?
Yes, quartz holds up very well against cutting thanks to its hardness. Use a cutting board to protect the surface and keep knives sharp. The non-porous quartz resists staining and bacteria from raw meats. Avoid cutting directly on the countertop.
How long do quartz countertops last?
With proper installation and care, quartz countertops can easily last 25 years or longer before needing replacement. The resins binding the quartz together do not break down or erode under normal conditions. Just avoid excessive heat or force that could chip the edges.
Can quartz countertops burn or scorch?
Quartz resins start to degrade around 300°F, so temperatures beyond that could scorch or discolor the surface. Briefly placing hot pans on quartz is fine, but use trivets or hot pads when handling extremely hot cookware. Avoid direct flames or burning cigarettes on the countertop.
Do quartz countertops need to be sealed?
Sealing is not required for quartz since it is non-porous. Some homeowners choose to apply sealers periodically to enhance stain resistance, but this is not mandatory. Proper cleaning and avoiding stains are more important than sealing for quartz care.
Conclusion
Quartz continues to grow in popularity for countertops thanks to its perfect balance of aesthetic appeal and practical performance. Made from abundant natural quartz aggregates bound with polymer resins, quartz offers exceptional durability, stain resistance, and low maintenance – ideal for the heavy use of kitchen counters. Following proper installation and care guidelines, quartz countertops can stay looking pristine for decades to come. So if you’re remodeling your kitchen, quartz certainly deserves strong consideration as a countertop material.