JEW­ELLERY 101

Rules For The Modern Man - - Rules For The Modern Man -

It may not look like an in­cred­i­ble ob­ject in its nat­u­ral form, but once a stone has been mined and cut to per­fec­tion, it trans­forms into an ob­ject of beauty that is pre­cious and unique.

Gem­stones arenʼt just some­thing that you pay a ton of cash for and de­liver to your other half in the hopes of ob­tain­ing for­give­ness for any wrong­do­ing. They can be a good in­vest­ment in cer­tain cases. They also bear dif­fer­ent qual­i­ties that you need to pay at­ten­tion to when choos­ing the right stone.

Hereʼs a quick es­sen­tial know-how, so you wonʼt be con­fused when you select your next stone.

DI­A­MONDS

The stan­dard four ʻCʼs do ap­ply in most gem­stones: Cut, clar­ity, caratage and colour. How­ever, dif­fer­ent fac­tors do come into play when dif­fer­ent stones are ex­am­ined.

Di­a­monds, the most pres­ti­gious of gem­stones, have a broad colour vari­a­tion. Coloured di­a­monds are the re­sult of im­pu­ri­ties in the stone, but that does not re­duce their value. The pres­ence of boron turns the crys­tal blue, and ni­tro­gen pro­duces yel­low tones. Pink and red di­a­monds come from struc­ture anom­alies as the di­a­mond is formed, while black di­a­monds are the re­sult of a pres­ence of other forms of car­bon than the crys­talline struc­ture. Fancy coloured di­a­monds have a dif­fer­ent form of grad­ing based on the rain­bow spec­trum and in­ten­sity, with pure colours ranked higher than mixes.

Colour­less di­a­monds, how­ever, are ranked from ʻ Dʼ to ʻZʼ, across a range that goes from colour­less to pale yel­low.

Fol­low­ing colour is the clar­ity that comes into play, which refers to the pres­ence of in­clu­sions or de­fects in the stone. There are a range of in­clu­sions such as in­ter­nal knots, other crys­tals, feath­ers, pin­points and beard­ing. Blem­ishes can also af­fect their grad­ing. The Ge­mo­log­i­cal In­sti­tute of America (GIA) has a stan­dard scale, with a per­fect stone as flaw­less (FL) down the scale as fol­low­ing: in­ter­nally flaw­less (IF), very very slightly in­cluded ( VVS), very slightly in­cluded ( VS), slightly in­cluded (SI) and in­cluded (I). Gen­er­ally speak­ing, anything above the VS cat­e­gory will be vir­tu­ally flaw­less to the naked eye. The In­ter­na­tional Di­a­mond Coun­cil ranks flaw­less di­a­monds as ʻ loupe cleanʼ.

Nat­u­rally, the less in­clu­sions, the rarer and more valu­able the di­a­mond, and the pricier it is per carat.

EMERALDS

The tra­di­tional pre­cious gem­stones are di­a­monds, emeralds, ru­bies and sap­phires. They are graded in the same man­ner as di­a­monds, but when it comes to clar­ity, they are ranked dif­fer­ently. In­clu­sions are cat­e­gorised as solid, liq­uid, gaseous or op­ti­cal in­clu­sions, and in the case of emeralds, three-phase in­clu­sions (with a solid, liq­uid and gaseous in­clu­sion) are highly priced. At the same time, op­ti­cal in­clu­sions such as trapiche, car­bon rays that ra­di­ate out from a cen­tre core, are the most prized. An­other rare ef­fect in emeralds is cha­toy­ancy or the catʼs eye, formed from fi­brous in­clu­sions or cav­i­ties in the stone that cre­ates a glow­ing line within the stone, hence its name. In­ten­sity of colour mat­ters as well in emeralds, and the even­ness of colour through­out the stone.

SAP­PHIRES

A vari­a­tion of corun­dum, sap­phires come in sev­eral shades and colours, which they are val­ued for ac­cord­ing to the in­ten­sity of the hue and the pres­ence of the se­condary colour that is present. Like emeralds, in­clu­sions are ex­am­ined by eye and the most ap­pre­ci­ated phe­nom­e­non in the gem­stone is as­ter­ism. Known as star sap­phires, this is due to the pres­ence of ru­tile that forms a six-or-12-ray pat­tern in light. The catʼs eye ef­fect can also be present. An­other rare type is the colour-change sap­phire, that offers dif­fer­ent shades in light.

THE SEMI-PRE­CIOUS

Con­trary to pop­u­lar be­lief, it is­nʼt just the pre­cious gems that hold value, though they are ap­pre­ci­ated for their rar­ity. The short­age of pre­cious stones means that semi-pre­cious gems are gar­ner­ing in­ter­est from col­lec­tors and brands. Tsa­vorite, a green gar­net that is only found in Tan­za­nia, rarely ex­ists in gem-qual­ity and is mea­sured for its in­ten­sity in colour and trans­parency. It be­came pop­u­lar in the last four decades, and yields in­cred­i­ble value to­day on the mar­ket.

Tan­zan­ite is even rarer and found in Tan­za­nia as well, hence its name. It has a unique tri-colour ef­fect that changes from sap­phire blue to bur­gundy depend­ing on the an­gle at which you view the ma­te­rial. The stone needs to be treated by heat for the tone to re­veal it­self, and is graded in qual­ity depend­ing on the hue and clar­ity. Due to the lim­i­ta­tions im­posed by the gov­ern­ment on its min­ing, it ap­pears at high prices on the jew­ellery mar­ket.

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