The Spotted Horse (L.887) occurrence is located northeast of Motherlode Creek, approximately 650 metres north-northwest of its junction with Boundary Creek.

The area is underlain by chert, siliceous argillite and siliclastic rocks of the Devonian to Permian Knob Hill Group and undivided sedimentary rocks of the Carboniferous to Permian Attwood Group, which have been intruded by granodiorite of the Cretaceous Anstey Pputon

The No.1 vein varies in width from 10 centimetres to approximately 1 metre and averages approximately 23 centimetres. It consists of pyrite, galena, sphalerite and occasional specks of chalcopyrite in a gangue of quartz. Magnetite is also reported. The vein strikes north 78 degrees west and dips from 53 to 15 degrees to the northeast. The country rock in the vicinity of the workings is granodiorite of the Cretaceous Anstey pluton. The mineralization in the No. 1 tunnel vein sometimes occurs in banded form and the intimately mixed layers of galena, sphalerite and pyrite are separated by thin layers of quartz.

The vein in the No.2 tunnel strikes northwest with a dip varying from 10 to 50 degrees northeast. On the face of the hill the vein can be traced for several hundred feet. The vein is approximately 7.5 centimetres thick and is almost barren. The vein pinches and swells up to 1.2 metres in width.

In 1924, several samples of ore yielded from 136.8 to 649.8 grams per tonne silver, 17 to 68 per cent lead and 4 to 12 per cent zinc (Minister of Mines Annual Report 1924, page 182).

In 1926, a 30-centimetre wide sample, taken across the vein where the mineralization was massive, assayed 1.37 grams per tonne gold, 137.14 grams per tonne silver, 11 per cent lead and 12 per cent zinc (Minister of Mines Annual Report 1926, page 212).

The Spotted Horse was Crown granted to the Boundary Falls Mining Co. Ltd in 1898. In 1923, the old workings were a starting place for new underground development. Work was documented in each year from 1923 to 1927.

By 1926 the Spotted Horse was being worked by the Silver Charm Mining and Milling Company and the property was renamed Silver Charm. Work amounted to two short tunnels and numerous shallow opencuts on the vein. The No.1 tunnel was approximately 27 metres long and the No.2 tunnel, which was approximately 14 metres lower in elevation, was approximately 6 metres long. In 1926, a total of 136 tonnes of ore was mined, from which 27.2 tons of shipping ore was sorted and approximately 81.6 tonnes of milling was saved for further treatment. The Spotted Horse was also worked for a short time in 1927.

In 1965, work was done on a quartz vein containing lenses of galena and pyrite. Sorted ore from drifting and stoping was shipped to the Trail smelter, but the operation was found to be uneconomic. Two shipments totalling 52.6 tonnes were made, after which the operation was shut down.