20分以下的钻石分级吗?

　　zuanshizhengshushizuanshipinzhizuizhijiezhengming，danhenduoxiaofeizhezaigoumaizuanshidouhuifaxian，yibanhenduoshangjiadouhuichengnuo30fenhuoyishangdezuanshidouhuipeibeishuangzhengshu，er20fenhuoyixiadezuanshiquezhichengnuopeibeiguojianzhengshu，zheibujinranghenduoxiaofeizheyihuo，weishenme20fenyixiadezuanshibunengpeibeigiazhengshuni？20fenyixiadezuanshifenjima?

　　baoyushiguojiabiaozhunzuanshifenjibiaozhundiyitiaobiaoming，zuanshifenjibiaozhundeshiyongfanwei：benbiaozhunguidingletianrande、weixiangqianjixiangqiandepaoguangzuanshidefenjiyuanze。dangyangpintongshimanzuyixiatiaojianshi，benbiaozhunshiyong。

　　1、weixiangqianpaoguangzuanshizhiliangdayudengyu0.0400g(0.20ct);xiangqianpaoguangzuanshizhiliangzai0.0400g(0.20cthan)zhi0.2000g(1.00cthan)zhijian。

　　2、weixiangqianjixiangqianpaoguangzuanshideyanseweiwusezhiqianhuang(he、hui)sexilie。

　　3、weixiangqianjixiangqianpaoguangzuanshideqiegongweibiaozhunyuanzuanxing。

　　4、weixiangqianjixiangqianpaoguangzuanshiweijingfumo、liexichongtiandengyouhuachuli。

　　5、zhiliangxiaoyu0.0400g(0.20ct)dexiangqianjiweixiangqianpaoguangzuanshifenjikecanzhaobenbiaozhunzhixing。

　　suoyi20fenyixiadezuanshishibufendengjide。20fenyixiadezuanshibuchudengjizhengshu，danshiyouguojianbiaozhundejiandingzhengshu。20fenyixiadezuanshijiandingzhengshushangbixuyou: riqi，bianhao，zongzhiliang(shizhong jinzhong) ，waiguantezheng，yanse。

　　20fenyixiadezuanshifenjima?yibanshichangshangmianxiaofenshudezuanshiduijingduqiegongdengdeyaoqiubugao，yinweijingduyansedouhenhaodezuanshishihennandede，suoyiruguozhendeyouzheiyangdezuanshi，yehuiqiemochengbijiaodadezuanshi，buhuishi20fenyixiade。qishiduiyu20fenyixiadezuanshishimeiyoushouzangjiazhide，zhinengzuoweizhuangshipin，suoyiguojianzhengshuduiyu20fenyixiadezuanshibufendengji。