Lithomancy or a divination practice of reading stones that are cast.
Grab a handful of tumbled stones that you are called to. Shake them in your hands. Place your hands above the center of the board or the template and drop the stones. Where the stones land, associate the part of the template along with the properties of the stones. If the stone falls on a line between two sides, use both for the stone. If it falls outside of the template, disregard it from the reading.
Here’s a link for a stone casting template.