Clark rare earth elements in the crust is 0.0153%, and common elements zinc, tin, cobalt content similar; Clark even smaller values thulium, lutetium, terbium, europium, holmium and the like, than bismuth, silver, mercury High content.
Although rare earth elements are widely distributed in the earth's crust, not all rare earth-bearing deposits meet the requirements of industrial development and utilization. According to the current technical level of mineral processing and extraction, the industrial indicators for rare earth deposits are listed in the following table.
Table 1 Industrial indicators of rare earth deposits
Deposit type | Boundary grade | Industrial grade | Available thickness m | Stone removal thickness, m |
With Bastnaesite, native monazite deposits | Ce 2 O 3 or R 2 O 3 0.5% | Ce 2 O 3 or R 2 O 3 1% | 1 to 2 | 2 |
Pegmatite and carbonate rock deposit xenotime, gadolinite etc. | Y 2 O 3 or R 2 O 3 | Y 2 O 3 or R 2 O 3 0.05 to 0.1% | 1 to 2 | 2 |
Monazite sand mine and weathering crust deposit | Monazite 100~200g∕m 3 | Monazite 300~500g∕m 3 | 1 | 1 to 2 |
Phosphonium ore deposit and weathering crust deposit | Phosphonium ore 30g∕m 3 | Phosphonium ore 50~70g∕m 3 | 0.5 to 1 | 2 |
If the rare earth element is recovered as a companion component in the deposit, the industrial index requirements may depend on the main useful elements in the deposit. For China's unique ion-adsorbed rare earth deposits, the industrial index requirements are still to be studied and formulated.
Alps Tact Switch,Navigation Use Switch,Square Thin Surface Switch,Surface Mount Push Button Switch
DA CHENG MINGHUA LIMITED , https://www.alpsswitch.com