Quick Search


Tibetan singing bowl music,sound healing, remove negative energy.

528hz solfreggio music -  Attract Wealth and Abundance, Manifest Money and Increase Luck



 
Your forum announcement here!

  Free Advertising Forums | Free Advertising Board | Post Free Ads Forum | Free Advertising Forums Directory | Best Free Advertising Methods | Advertising Forums > Post Your Free Ads Here in English for Advertising .Adult and gambling websites NOT accepted. > Post Your Business Ops Here

Post Your Business Ops Here This section is for posting your free classified ads about different work at home and home based business opportunities.

Reply
 
Thread Tools Display Modes
Old 05-07-2011, 07:35 AM   #1
djd1mfng
 
Posts: n/a
Default

跟着人们生涯程度的一直进步,穿着金饰品的人越来越多了,购置时,人们总想买纯一点的,nike basketball shoes,全纯的叫足金即真金,nike hyperdunk 2010 shoes。真金金光闪闪,比重19.3(克/厘米3),不怕腐化,千百年后其色纹丝不变。真金固然闪闪发光,但闪金光的不必定是真金,如愚人金跟人造仿 金(如氮化钛等。)

愚人金是指能闪烁金黄色的黄铁矿(FeS2)或黄铜矿(CuFeS2)的矿石,它们常以迷人的姿色愚弄缺少 矿物常识的人而得其诨名。

愚人金、仿金跟真金色泽无二,虚实难辨。但它们一遇到试金石,其“庐山真面目”便裸露无遗。看 来,discount kobe shoes,试金石倒的神秘,实在,它不外是天然界极一般的石头,色呈灰黑,状如鹅卵,通称辉绿石或石英岩其化学成份 重要是SiO2,硬度较大,因久经风化逐成鹅卵状。测验时,只有把受试物在试金石上一划,便暴露无遗:黄铁 矿划出的条痕是玄色的:黄铜矿划出的条痕是墨绿色的;而真金呢?在试金石上留下的划痕,再出其“庐山真面” -金黄色。

“金无足赤”。自然黄金尚且不尽相对纯,更何况黄金稀贵,所以,不少金饰品都是在金里增加一些铜 、银, 把它做成合金。人们选购时,这就面临一个如何鉴定黄金同一纯度,断定其成色(含金量)的问题,nba basketball shoes。凭借试金石的“火眼金睛”,不仅能辨别黄金的真伪;还能识破黄金的优劣(以“K”为单位,以24K…10 0%为优;18K…75%为次,bryant shoes on sale;12K…50%为劣)这是由于不同成色的金饰品,色彩稍有差异。人们当时按比例精制出不同含金量的尺度金 条,逐一在试金石上划出确知含量的色痕,再拿待测的金饰物在统一试金石上划痕,两相比拟,最后由教训丰盛的 内行断定成色。此法简略位易行,但有一定的误差, 必需寻找更准确的方式,选用“眼光更为灵敏”的仪器。
随着迷信技巧的发展,kobe bryant Shoes,国外发现一种激光试金仪。把激光束照耀金、合金或仿金,分辨化为蒸气,浮现不同光谱线及其强度,从而甄别 无误,操作简捷,也不必担忧损耗黄金,检修时,用激光打的刀比针尖还小,样品丧失不足十亿分之一克,真是微 不足道,颇受顾客和珠宝商的欢送,这种撩开不拘一格“庐山真面”的金饰品的仪器,堪称货真价实的“试金石” 。
  Reply With Quote

Sponsored Links
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off


All times are GMT. The time now is 11:13 PM.

 

Powered by vBulletin Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Free Advertising Forums | Free Advertising Message Boards | Post Free Ads Forum