Opal

The opal is a beau­ti­ful gem­stone ex­trac­ted from the li­quid mass of flinty soil, and it usu­ally pre­serves some hu­mid­ity (6-10 per­cent) after crys­tal­liz­a­tion. Opal hues are al­ways unique and un­re­peat­able due to vari­ous ad­mix­tures form­ing the tex­ture. The ba­sic opal min­er­al can be col­or­less, rose, brown, am­ber-yel­low, or red. Noble opals (the ones with the hu­mid­ity level men­tioned above) pro­duce at­tract­ive rain­bow-like col­ors.

Opal types are de­term­ined by the ba­sic min­er­al from which they were formed. Their min­er­al ori­gin also af­fects cer­tain opal fea­tures such as col­or, clar­ity, shin­ing and solid­ity. There are ig­noble opals formed of clint (flinty rocks); ligneous (woody) opals formed of bot­an­olite (a plant turned to stone); com­mon opals that are semi­pre­cious gems; and noble opals, which are pre­cious gems. Noble opals are the only to be used for jew­elry be­cause of their op­tic­al fea­tures.

Opals are di­vided in­to large num­ber of groups ac­cord­ing to their col­or. The best known opals are fire opals (from red to re­dish-yel­low stones), wax opals (trans­par­ent light blue), hy­al­ite opals (col­or­less, misty-blue, or sky-blue trans­par­ent stones), hy­dro­phane (white, opaque, highly por­ous stones), jelly opals (al­most col­or­less, blu­ish stones), gi­ra­sols (or­ange trans­par­ent stones), am­ber opals (trans­par­ent brown­ish or yel­low­ish stones), cach­along opals (opaque, highly por­ous stones), Per­uvi­an opals (blu­ish-green or or­ange stones), and prase opals (apple-green stones). Gen­er­ally, there are about a hun­dred opal types di­vided ac­cord­ing to col­or and trans­par­ence.

Opals are very fra­gile stones and need spe­cial care. The most dan­ger­ous risk for these stones is de­hyd­ra­tion. Opals loose their glit­ter when their wa­ter evap­or­ates. It is also harm­ful for the stones to be ex­posed to dry hot air or cold air as well as to tem­per­at­ure swings be­cause the stone can simply crack. It is not re­com­men­ded to take opals on a plane be­cause changes in air pres­sure are harm­ful to the opal’s struc­ture. Opals needs hy­dra­tion peri­od­ic­ally so it’s ne­ces­sary to pol­ish them with a wet or oiled piece of fab­ric to pre­serve their shin­ing beauty.

The biggest known opal is the An­damooka Desert Flame weigh­ing 6.85 kg (15 pounds) or 34,250 car­at. The next biggest is the Jupiter-5 opal. Both stones were found in Aus­tralia. The "Olympic Aus­tral­is" is re­por­ted to be the largest and most valu­able opal ever found. It was found in the 1956 at the fam­ous "Eight Mile" opal field in Coober Pedy, South Wales, Aus­tralia and it weighs 17,000 car­ats (3,450g or 7.6 pounds).

Since the an­cient times, the opal has been as­so­ci­ated with faith and piety. In Europe, this stone has been a sym­bol of fam­ily hap­pi­ness, con­fid­ence, etern­al love, and pur­ity of soul. A curi­ous fact is that, at the same time in Europe, the opal also sym­bol­ized the charm­ing in­con­stancy of the fe­male love - chan­ging like winds in the spring. Opal is re­garded as a pro­tect­or of those who pos­sess ma­gic­al powers, those who have strong spir­its, and those who try to puri­fy their souls. On the oth­er hand, the opal is dan­ger­ous for dream­ers and fanci­ful per­sons as it is be­lieved to dam­age men­tal health and even cause schizo­phrenia.

Opal is a very de­cept­ive and ca­pri­cious stone so it is not re­com­men­ded for every day wear­ing. It is strongly re­com­men­ded to switch fin­gers when wear­ing an opal in a ring. Opals are be­lieved to help people ad­dicted to sui­cid­al thoughts and to help in solv­ing com­plic­ated prob­lems with life.