The rift, grain, and hardway are planes approximately at right angles to one another along which granites fail most easily under tension. The rift is due to the peculiar properties of quartz and is approximately horizontal in most "Laurentian" granites. The grain is in the direction of foliation. The hardway may be a direction at right angles to the other two or may be determined by tectonic cracks or other features. The joints tend to be more consistent in attitudes than the cleavage.

This content is PDF only. Please click on the PDF icon to access.

First Page Preview

First page PDF preview
You do not currently have access to this article.