Dunite counter top.
Later walking to the post office and courthouse for mail and research I saw a dunite bench along the Whatcom Creek trail.
Dunite bench along Whatcom Creek trail
Dunite is the from the earth's mantle and consists primarily of olivine. Dunite and other rocks with high iron and magnesium content are called ultramafite. The Twin Sisiters range in the Northwest Cascades consists almost entirely of dunite. The range is essentially a huge block of the earth's mantle somehow exhumed and thrust up into the Northwest Cascade Range (twin-sisters-range-and-dunite). A quarry on the lower slopes of the range extracts dunite as a liner for high temperature incinerators as olivine has a high melting temperature (its from the mantle of the earth). The rock is attractive so is also commonly used as a decorative stone. The downside of its use as decorative rock is that it is very hard and very massive with a specific gravity approximately twice that of average rocks.
Ultramafic rocks such as dunite have gained interest as a means of sequestration of CO2 by the reaction Mg2SiO4 (Mg Olivine) + 2CO2 ---> 2MgCO3 (magnesite) + SiO2. See Danae and others (2009) for an over view of site selection and Koukouzas and others (2009) for a bench study.
In both examples above I like the orange weathering rind left on the edge of the counter and bench. This is the same color as the Twin Sisters range when the range is not mantled in snow as it was last week when I saw the range from near the South Fork Nooksack Valley.
Twin Sisters viewed from Saxon