opalized
/ˈəʊpəlʌɪzd/(also opalised)
adjective
(Especially of a fossil) converted into opal, or a substance resembling opal; rendered opalescent.
Origin
Early 19th century; earliest use found in John Pinkerton (1758–1826), historian and poet. From opal + -ized. Compare French opalisé converted into opal, having the form of opal, having the colour of opal.