solid homogeneous inorganic substances occurring in nature having a definite chemical composition

a multivalent nonmetallic element of the nitrogen family that occurs commonly in inorganic phosphate rocks and as organic phosphates in all living cells; is highly reactive and occurs in several allotropic forms

a metallic element of the rare earth group; used in lasers; occurs in apatite and monazite and xenotime and ytterbite

a soft silvery metallic element of the rare earth group; isotope 170 emits X-rays and is used in small portable X-ray machines; it occurs in monazite and apatite and xenotime

a form of apatite in which fluorine predominates over chlorine

a multivalent nonmetallic element of the nitrogen family that occurs commonly in inorganic phosphate rocks and as organic phosphates in all living cells; is highly reactive and occurs in several allotropic forms

a metallic element of the rare earth group; used in lasers; occurs in apatite and monazite and xenotime and ytterbite

a soft silvery metallic element of the rare earth group; isotope 170 emits X-rays and is used in small portable X-ray machines; it occurs in monazite and apatite and xenotime