A deposit of tufa is situated in the bed, and just north, of a small creek flowing under Highway 1, about 1 kilometre north of the Boston Bar post office.

The deposit stretches discontinuously eastward from the highway along the creek for 400 metres, attaining a maximum width of 46 metres and a maximum thickness of 1.5 metres. A roadcut on the highway beside the creek exposes tufa over a width of 30 metres. As of 1950, tufa was still being deposited in the creek bed.

A grab sample of the tufa contained 54.6 per cent CaO, 0.14 per cent MgO, 0.87 per cent SiO2, 0.042 per cent iron, 0.1 per cent fluorine and 42.86 per cent CO2 (McCammon, 1951 - Industrial Minerals File).

The deposit was held by Mr. Graixte and Fred Bilow of The Canyon Cement Works in 1950. No development work has been done and no recent information concerning this occurrence is available.