Brief: Natural quartz (not to be mistaken with quartz aggregate material such as caesar stone) has become more and more popular over the last few years. We do not consider it a ‘mainstream’ product due to cost, and it is rarely encountered outside of custom applications. Aesthetically, I consider some natural quartz the epitome of beauty in a slab of stone. Quartz slabs often exhibit a subtle transparency, filled with beautiful crystalline veins, and often with very consistent colouring. The main downfall of quartz is there is no sure way to know if it will etch, we’ve encountered quartz counters that were impervious to etching and others that would respond to acid like your average marble. There are many resources/testimonials available online, we recommend thorough research and to test your slab to be certain it is etch resistant if that is your aim. Take time to express these concerns to your supplier before purchasing slabs. Our research suggests darker slabs of quartz to be less prone to etching than lighter slabs.
Susceptibility to Etching: (read above)
Hardness: 7 (Mohs scale):
Quartz is consistently gauged to be as hard or slightly harder and more resistant to scratching than granite. Like onyx, if a slab is prone to etching, etched areas will likely be less scratch resistant due to weathering.
Like granite, quartz porosity will vary slab to slab. Generally speaking, quartz is much less porous than marble/limestone, but still requires sealing. Quartz is much less prone to the discolouration seen in poorly maintained marble, but deposits of minerals within the quartz can still cause discolouration if not properly maintained.
Quartz is often on par with granite when it comes to repairs, however it has some unpredictable qualities. Quartz often has deposits of other minerals which do not polish to the same lustre as the rest of the slab, the physical pressure applied during original manufacturing cannot be replicated on site, making matching the original luster difficult in some slabs. To date we’ve managed to always match the finish, but are aware of this limitation and feel it is worth mentioning. Due to the transparent nature of quartz, clear epoxies with longer curing times may be necessary, adding time/cost to chip and crack repairs.
Brief: Onyx is a dramatic, translucent material that has always been used for it’s unique patterning (banding) and dynamic colouration. We usually see this material used as furniture tops and powder room/bath counter tops. Onyx is on par with marble with regards to maintenance needs, which is why we rarely see it used in kitchens or as a floor tile in high traffic areas. Onyx looks best polished to a high gloss finish, as this reveals is transparency, unfortunately this means there is no low maintenance solution if you choose to use it in a vulnerable area of your home. Due to the transparency of onyx, it is a prime candidate for backlit applications, including countertop islands, reception tops, or as a unique wall covering. Back lighting will accentuate the fine concentric layers of mineral deposits (banding) within the stone and reveal its depth. Expect this material to cost more than your average slab of crema marfil (marble).
Susceptibility to Etching: 10
Onyx is very reactive to acids, it will etch easily.
Hardness: 6-7 (Mohs scale):
Onyx is rated as being as hard as granite. While it may be hard like granite, it is still very susceptible to etching and softening due to introduction of acids, this is called weathering. For example, an onyx floor that has been washed with vinegar or other acidic cleaners will be easier to scratch than in it’s polished (un-weathered) form.
Onyx is considered a porous material, and should be treated the same as marble with regards to your sealing schedule.
The tools and compounds used to polish marble are also used with onyx, and the material itself responds very well. Due to its hardness, some extra smoothing techniques are required to bring it to a full gloss polish. Because the material is translucent, clear epoxies with longer curing times may be needed to repair chips or cracks, this can also add to cost.
Brief: Soapstone is currently trending south of the border for its unique rustic look and resistance to etching. Soapstone is naturally non-porous and requires little professional maintenance if any at all if this rustic material suits your aesthetic preferences. If you are looking for a high gloss polished counter, or a scratch resistant surface, we suggest avoiding soapstone. When choosing this material it is very important to know the specific hardness based on where it originated, as soapstone softness can vary drastically region to region.
Susceptibility to Etching: 0
Similar to slate, the material itself will not etch, but spills that react with applied mineral oil or wax may appear lighter than the surrounding stone, imitating an etch. Re-application of mineral oil/wax should hide the discolouration.
Soapstone is made primarily of talc, making some variants incredibly susceptible to scratching, it is important to work with your stone supplier when choosing a slab to ensure it performs to your expectations.
Soapstone is a non-porous material by nature, it will not require any professional sealing beyond the use of mineral oil or wax if preferred for aesthetic reasons. Application of oil or wax is not required, but will darken the stone naturally and is recoatable if an area becomes worn or damaged.
Soapstone is very soft, and thus easy to grind and resurface and is generally left with a patina finish. Because the minerals in soapstone do not react well with traditional marble polishing compounds, all re-surfacing must be performed mechanically (no chemical assistance) which can add to cost. If the soapstone is being maintained with mineral oil, re-application of the oil often hides the “chalkiness” caused by scratches. Homeowners who pick soapstone are generally more inclined to maintain their counters themselves, as mineral oil application is required more often than sealing is required on a marble counter. Most cases where etching is described are not actual etching, rather a reaction between the “etch causing product” and the mineral oil or wax, reapplication of the oil/wax should restore the area to its dark tone.
Brief: Slate is the only material mentioned that is not a candidate for resurfacing. The surface of a slate tile is it’s natural finish, which consists of a subtle rough but generally consistent texturing. Because it is relatively soft compared to even marble, slate is often coated with topical finishes to protect it from turning chalky and scratched. Over time this floor finish may fail or collect dirt at which point it can be stripped and sealed with a colour enhancer or even a clear penetrating sealer, in most cases we recommend non-topical coatings. The recommended method of sealing depends on the location of the material, traffic, and desired appearance.
Susceptibility to Etching: 0
Slate does not etch, but topical coatings generally found on slate may react to solvents or other chemicals, lightening the area and looking similar to an etch.
Hardness: 3-4 (Mohs scale):
Slate is quite soft, and will display scratching and wear relatively quickly when exposed to the elements. This isn’t necessarily bad, as it does wear consistently if a rustic appearance is desired.
Slate is not particularly porous, but this varies from where it is sourced. Since slate does absorb sealer readily (both clear and colour enhanced penetrating sealers) it is safe to assume oil and other contaminants will quickly penetrate into most raw slate surfaces. If a topical coating is applied sealing is not needed as often, but once dirt has penetrated into the topical finish or discolouration occurs, stripping the floor finish is required before new sealer can be applied.
Since slate tile is generally left in it’s raw form, resurfacing is not possible. Scratched or high points cannot be removed without making the affected area look drastically different from the original finish. Most of our slate repairs consist of stripping topical coatings and either applying a penetrating sealer (both clear or colour enhanced) or re-applying a thin layer of topical coating if the customer prefers a glossier finish. Chips and cracks can be repaired with a colour matched epoxy, but again will not match the natural finish.