Slate floor tile is a type of natural stone that is quarried from the side of mountains or taken from the earth. A finely grained, homogeneous, metamorphic rock, it is named for the way the material forms in plains, like sheets resting one atop the other, compressed under great pressure to create a powerful bond. While slate is one of many natural stone floor tiles available, there are also different types of slate, each with its own look and characteristics. Slate has its pros and cons as a floor tile. Its natural beauty makes it a desirable flooring, but it also requires professional installation and maintenance.
Slate's Manufacturing Process
The raw stone used to produce slate floor tile can be found in mountains around the world, with productive quarries in Europe, Asia, and across the Americas. The region that the material is sourced from will determine the constituent chemicals present during the formation of the stone. The chemicals affect the look and characteristics of the slate in its finished state.
Slate is generally sliced from the earth in the form of rough, massive slabs. These slabs are then cut down into smaller, more manageable slabs and tiles. Pieces reserved for tile are then gauged (evened out for installation). The surface of the slate can also be further refined or left in its natural state. Slabs are generally used as countertops, with smaller, thinner tiles of varying sizes used for flooring.
There are three ecological concerns about slate:
- Slate is very heavy and fuel costs are higher when transporting the material to a job site.
- Regions with fewer mining regulations can lead to unsafe working conditions.
- Aggressive mining of slate can cause physical damage to the land.
Slate Floor Tile Options
Slate floor tiles come in two distinctive finishes. One type of finish may fit a rustic interior while another may blend in better in a contemporary setting.
All slate that will be floor tiles is gauged. At the time it is extracted, the slate is a rough, broken material like you'd expect from any rock found on the ground. When refined into tiles, natural stone generally goes through a process where the material is gauged, which refers to flattening the back in order to help the tile set into the mortar during installation.
What is Ungauged Slate?
If the back of the slate tile is not flattened, then both sides will be rough and bumpy. Known as ungauged slate, these materials are usually reserved for outdoor applications where they can be sunk into the ground for stepping stones.
After being sliced into tiles, slate is still naturally going to be bumpy and broken. In many cases, this is desirable because it makes the material feel more rugged and earthy. When the surface is left unrefined, it is called "cleft," although the term “natural” is also often used to refer to it looking more like it would in its untouched mountain-born state. Cleft slate has great traction, even when wet, but if the ridges are too extreme, it can be uncomfortable to walk on barefoot.
In some cases, slate tiles will have a honed finish, meaning that they're polished to the point of a perfectly smooth surface, but without glossiness. This slate's dimensionality and colors become more muted when honed, though the material does retain the same basic hues. When you touch the face of a honed piece of slate, you'll feel some traction, though less so than cleft slate floors. Another effect of honing is that tiles will be more likely to show stains and will be easier to scratch.
Glossy Finishes on Slate
Slate is too brittle a material to withstand the intense polishing it has to go through to achieve a high-gloss look. However, the application of enhancing sealers on honed tile can give a slate floor a glossy finish.
Indoor and outdoor slate floor tiles look like they sprouted from the landscape thanks to the material's naturally rich palette of earthy colors. Colors can range from lighter tans to deeper shades of copper, red, navy, sage, and black. You'll find tiles with all or one color, depending on the look you'd like.
Solid slate floor tiles are predominantly one color all the way through. The consistency of hue and tone across a single tile, and across tile lots, can vary to differing degrees which can affect your floor if you need to replace a slate tile. Floors made from solid-colored stone materials tend to be more formal, subdued, and monochromatic. However, the unity of appearance makes it easier to see dirt while small stains or scratches will be more visible.
Many slate floor tiles are multicolored, often with wildly contrasting shades and veining on one tile. Multicolored stones do not look uniform when installed, but the floors are eye-catching and dramatic. There are numerous multicolored slate lines on the market, but the veins of material tend to vary over time.