Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
The frequency of aggregates of various sizes in grade 1 and grade 4 cases. This graph shows the relative frequencies of aggregates based on their size using increments in their area of 15 nm2. Small aggregates are more frequent in earlier grade cases.
