Zaɓin opal yana dogara ne akan dalilai kamar launi, matsayi na eyeliner, siffar da nauyin gemstones.Don kyawawan duwatsu masu daraja na ido na cat, layin ido na cat ya kamata ya zama bakin ciki da kunkuntar tare da iyakoki bayyananne;ya kamata a buɗe idanu kuma a rufe a hankali don nuna haske mai rai;launi na idon cat ya kamata ya kasance da bambanci da baya;kuma layin ido na cat yakamata ya kasance a tsakiyar baka.Lokacin siye, ya kamata ku bambanta opal daga sauran duwatsu masu daraja da kuliyoyi na wucin gadi bisa ga halayen ganowa, kuma ku sayi opal na gaske.

Kamar sauran duwatsu masu daraja, mafi girman opal, mafi wuyar shi ne, don haka nauyi har yanzu yana ɗaya daga cikin abubuwan da ake bukata don kimanta opal.Amma mafi mahimmancin abin da ke shafar opal shine launi, yanayin da kuma ko'ina na eyeliner.

Mafi kyawun launuka na opal sune kore mai launin rawaya mai ƙarfi, tans da rawaya na zuma, sannan sai launin kore sannan kuma launin ruwan kasa kaɗan.Fararen rawaya masu launin rawaya da farare sosai ba su da daraja.Mafi munin su ne variegated da launin toka.

Mafi kyawun gashin ido na opal ya kamata ya zama kunkuntar, ma'anar da kyau, mai haske, kuma a tsakiya a kan gemstone.Dangane da kalar gashin ido, wasu na son kalar goshin silvery, yayin da wasu suka fi son zinare, yayin da layin kore da shudi-fari sun fi yin sakaci.Launin jiki ba shi da launin toka, sau da yawa tare da launin shuɗi ko shuɗi-launin toka.Duk da haka, duk abin da launi, yana da mahimmanci cewa eyeliner ya bambanta da baya kuma ya bayyana mai tsabta.Idanun ya kamata su iya buɗewa, mafi girma mafi kyau, kuma ya kamata su kasance masu kaifi idan an rufe su.

Fasahar sarrafawa (musamman ma'auni na daidaitawa) shima muhimmin abu ne wajen kimanta opals.Domin yin cikakken amfani da dutse na asali, manufar barin shi mai kauri shine ƙara nauyi da kuma sayar da kuɗi.Amma sakamakon ya ci tura, asymmetry ya shafi kyawun idon cat sosai, kuma babu wanda ya ba da farashi mai yawa.Hanyar da ta dace ita ce kiyaye kauri mai dacewa a ƙasa da waistline na gemstone kuma a niƙa shi a cikin ƙaramin baka.Don ci gaba da ƙananan kusurwa, wannan zai taimaka wajen sa gemstone ya kafa da ƙarfi a kan goyon baya.