What a volcanic rock gives you
Most building stone was laid down in water and carries the record of that: bedding planes in a limestone, veining in a marble, layers in a travertine. Basalt has none of them, because it never settled out of anything.
What it has instead is uniformity. A piece of basalt looks the same as the next piece and the same in every direction, which is a property no sedimentary or metamorphic stone can offer. There is no right way up and no grain to work with or against.
Basaltina and where it comes from
The series here is Basaltina, which is the trade name for the lava stone quarried north of Rome in the volcanic country around Viterbo.
It is a slightly lighter and more porous basalt than the dense black varieties, with a warm mid gray tone and a fine even texture. The Romans used the harder local basalt for road surfaces and the softer volcanic stones for building, which is roughly the same distinction the trade still makes.
The finishes are all mechanical
Honed, bush hammered and chiseled make up this small range, and every one of them is something done to the stone with a tool rather than a chemical or a coating.
Bush hammering strikes the face repeatedly with a pointed head, leaving an even pocked texture. Chiseling cuts furrows across it. Honing grinds it flat. A basalt takes all three cleanly because it is uniform: there is no soft layer to break away and no vein to follow.
Why it does not take a polish
Basalt can be polished and it is rarely worth doing. The rock has no figure, so a polish has nothing to reveal, and what it produces is a flat gray mirror.
Marble is polished to bring up the depth in its crystals and the contrast of its veining. Take away both and the polish is only a reflection. That is why this range runs to textured faces instead, where the surface is the interest rather than the pattern.
The formats and the thickness
12x24 throughout, at 5/8 and 3/8 inch, which is thicker than the 3/8 most marble field tile uses.
Five eighths of an inch is a paving thickness rather than a tile one, and it follows what the stone is for. A basalt floor is a hard-wearing surface first and a decorative one second, and it stands higher than a thinner tile in the next room. The 12x24 format is worth noting too: a stone with no figure gains nothing from a large piece, so the size is chosen for the joint count rather than to show anything off.
Where basalt goes
A floor, an entry, a terrace, a courtyard, a stair and a wall where the texture of a bush hammered or chiseled face is the point.
It is the stone for a project that wants gray with no pattern in it whatsoever, which is a narrower requirement than it sounds and one that almost nothing else meets. Gray tile and mosaic is the color, and slate look tile the nearest dark textured effect.
