Sand Gauge Chart
Description:-

Sand Gauge has nine granule patches which are firmly attached to the handy 3.5 x 2.5in (89 x 64mm) water-resistant plastic card to assist in defining roundness and size of particles from 2mm very coarse sand to 1/16mm silt. 
A checklist is included to assist in making field notes and defining bed thickness. 
Particle Shape Panels. Angular; sub-angular; sub-rounded and rounded.
The flip side of the chart has tables of geologic age and carbonate classification information.
Sample Panels. Very coarse; coarse; medium; fine; very fine; silt.
 

Sand Gauge Chart