Words to Describe impurities

How impurities often is described ("________ impurities")

• forming
• acidic
• polar
• gaseous
• shallow
• light
• molecular
• principal
• unwanted
• organic
• objectionable
• soluble
• solid
• residual
• ferromagnetic
• chief
• certain
• colored
• toxic
• insoluble
• type
• various
• isoelectronic
• deep
• accidental
• interstitial
• adsorbed
• containing
• extraneous
• radiochemical
• common
• heavy
• fewer
• unknown
• minor
• nonmetallic
• active
• metallic
• gross
• inorganic
• chemical
• substitutional
• mechanical
• usual
• earthy
• visible
• deleterious
• atmospheric
• injurious
• paramagnetic
• undesirable
• ionic
• metal
• dangerous
• slight
• lighter
• related
• possible
• volatile
• nonmagnetic
• nonvolatile
• coarse
• other
• harmful
• minute
• neutral
• magnetic
• level