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Columbia River Sand, US-Canada Boundary

Columbia River Sand, US-Canada Boundary

Two blast furnace slag particles are present in this sample. They are evident by the lack of reflection in the opaque particles. The black blast furnace slag particles are glass with inclusions. They are not conductive and have low refractive indices relative to the black metal oxides. The black metal oxides are much better reflectors because they tend to be semi-conductors and have real refractive indices far from 1.680, the mounting medium used in this case.

Transmitted Circular Polarized Light and Reflected Darkfield Illumination


This deposit sample was part of a study for the distribution of slag particles introduce into the Columbia River from a smelter upstream. A strandline deposit forms at a special boundary or interface. That boundary can be the site of wave action, current, or subsurface characteristics. Strandline deposits form on beaches and at the leading or trailing edge of air classified sand deposits.

Significance in the Environment:

Characteristic Features:

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