Where the green comes from
Limestone is made from the compacted remains of sea life. Mixed in with that material are clay minerals, and two of them, glauconite and chlorite, are green.
Where the sea floor carried enough of either, the limestone that resulted came out green rather than the cream or gray that iron and carbon usually produce. It is an uncommon combination, which is why green limestone is a short list wherever it is sold.
A green with no brightness in it
These are not the greens a glaze produces. A mineral green in a sedimentary rock is muted, slightly gray and closer to sage or olive than to anything saturated.
That restraint is the reason the stone gets used at all. A green ceramic makes a statement; a green limestone reads as a neutral that happens to lean green, which is a much easier thing to build a room around. The made greens are in green backsplash tile.
Honed, as limestone always is
Both pieces here are honed, which is the finish limestone is normally supplied in.
The stone will take a polish and rarely holds one, because its grain is softer and more open than a marble's. Honing gives an even matte surface that shows the color and the texture without asking the material to behave like something it is not. Limestone tile is the whole quarried material.
Seagrass and the trade names
The names here are seagrass and verde, and both describe the color rather than a quarry, which is normal for a stone this rare.
Seagrass in particular is a widely used trade name for green limestones with a banded, slightly directional figure, and it turns up under that name from more than one source. The material field on the individual product page is where the stone itself is stated.
Why it is so hard to find
Two products is not an oversight in the buying. Green limestone occurs in small quantities and the beds that produce it are neither large nor widely distributed.
It is also a stone that rarely reaches tile format. Where a quarry produces a small amount of an unusual color, the material tends to go into slabs and cut-to-size work, where the price supports the handling, rather than into boxes of field tile. A green limestone tile is a relatively rare thing to be able to buy at all.
The formats
12x12 and 12x24 at 3/8 inch, which is the standard thickness for stone field tile.
Two ordinary sizes, which suits a stone bought for its color. A green limestone is already doing something unusual, and a large or unusual format on top of that gives a room two things to absorb at once.
Where green limestone goes
A bathroom floor, a hall, a shower wall, a fireplace surround and a band inside a cream or gray field, where the two stones are geologically the same material at different mineral content.
Limestone mosaics covers the sheets and beige tile and mosaic the warm neutrals it sits most naturally beside.
