The Hed & [and] Strand mine was developed by an adit and drifts on stibnite-bearing quartz veins in metamorphic rocks. The main vein was intersected 90 feet in from the portal of the adit; it strikes N45E and dips 48 N. At this point, the vein was followed by a 100-foot drift to the northeast and a 140-foot drift to the southwest (Mertie, 1918 [B 662-I, p. 425-449]). At the face of the 100-foot drift, the vein was about 2 feet wide and composed mostly of sheared schist with thin seams of stibnite on the hanging and foot walls. Where intersected in the adit, the vein was 4 feet wide; it consisted of white quartz and stibnite, with stibnite forming a footwall mass about 2 feet thick. A second subparallel vein was found 190 feet from the adit portal; it was drifted on for 170 feet. Lower grade material contains quartz and pyrite; Brooks (1916, p. 54-56) reported a mineralized mica schist with calcite, pyrite, and arsenopyrite. Mertie (1918, p. 438) reported that quartz with stibnite, exposed in the creek near the mine, assayed about 0.30 ounce of gold per ton; the associated stibnite contained about 0.1 ounce of gold per ton. The veins pinch and swell, and, as is typical of simple stibnite veins, the ore occurs in pods and kidneys (Bliss and Orris, 1986, p. 183-186).

About 106 tons of stibnite ore were mined and shipped in 1915 and 1916. This ore had a low gold content. Development continued at the mine in the late 1920s and early 1930s. When Anderson (1947) visited the mine in about 1943, about 10 tons of 30 percent antimony ore were on the dumps and about 30 to 40 tons were exposed in mine workings. At that time, there were about 1,000 feet of accessible mine workings.

The schist in the adit had a strike of about N15W and dipped at a low angle to the northeast. The main workings appear to lie within quartz-mica schist and a feldspar-rich epidote-bearing schist near a contact with massive marble (Bundtzen and others, 1994). The epidote-bearing schist may be part of a regional mafic metavolcanic assemblage that has an Ordovician protolith (Till and Dumoulin, 1994). Hummel (1962 [MF 248]) mapped an approximately east-west high-angle fault in Dahl Creek; the fault is upthrown on the south side. Earlier authors, including Mertie (1918 [B 662-I, p. 425-449]) and Cathcart (1922), noted a nearby metamorphosed granite body as possibly related to the mineralization, and Hummel (1962 [MF 248]) showed a small granite orthogneiss on the ridge east of the prospect. Granitic orthogneisses mapped by Bundtzen and others (1994) are about 1 mile north and 1 mile south of the prospect. The area is too complex to decipher with 1:63,360-scale mapping.