| Various attempts were made to date bulk zircon fractions from a number of granitoid rocks. |
| Eighteen analyses of detrital zircon and one of monazite were carried out for the late Silurian sandstone. |
| Reducing iron oxide levels to 0.07 percent will allow the zircon to meet premium grade specifications. |
| A honey-colored to brown zircon continues to be mined that can be heat-treated to lighten the color. |
| Rare earth element distributions in the zircons and garnets strongly suggest that the zircon overgrowths formed in equilibrium with garnet. |
| Quartz is associated most commonly with aegirine and potassium feldspar as well as zircon. |
