翡翠（jadeite）， 也称翡翠玉、翠玉、缅甸玉，是玉的一种。翡翠的正确定义是以硬玉矿物为主的辉石类矿物组成的纤维状集合体 。但是翡翠并不等于硬玉 。翡翠是在地质作用下形成的达到玉级的石质多晶集合体，主要由硬玉或硬玉及钠质（钠铬辉石）和钠钙质辉石（绿辉石）组成，可含有角闪石、长石、铬铁矿、褐铁矿等。
翡翠的英语单词是Jadeite jade ，Jadeite 指硬玉，翡翠是硬玉的一种。
翡翠的英语介绍
Jadeite is a pyroxene mineral with composition NaAlSi2O6.It is monoclinic.It has a Mohs hardness of about 6.5 to 7.0 depending on the composition.The mineral is dense,with a specific gravity of about 3.4.
The name jadeite is derived(via French:l'ejade and Latin:ilia[5])from the Spanish phrase"piedra de ijada"which means"stone of the side".The Latin version of the name,lapis nephriticus,is the origin of the term nephrite,which is also a variety of jade.
Jadeite forms solid solutions with other pyroxene endmembers such as augite and diopside(CaMg-rich endmembers),aegirine(NaFe endmember),and kosmochlor(NaCr endmember).Pyroxenes rich in both the jadeite and augite endmembers are known as omphacite.Jadeite is formed in metamorphic rocks under high pressure and relatively low temperature conditions.Albite(NaAlSi3O8)is a common mineral of the Earth's crust,and it has a specific gravity of about 2.6,much less than that of jadeite.With increasing pressure,albite breaks down to form the high-pressure assemblage of jadeite plus quartz.Minerals associated with jadeite include:glaucophane,lawsonite,muscovite,aragonite,serpentine and quartz.[clarification needed]
Rocks that consist almost entirely of jadeite are called jadeitite.In all well-documented occurrences,jadeitite appears to have formed from subduction zone fluids in association with serpentinite.Jadeitite is resistant to weathering,and boulders of jadeitite released from the serpentine-rich environments in which they formed are found in a variety of environments.
