人妻系列无码专区久久五月天丨精品久久亚洲中文无码丨国产精品爽爽久久久久久蜜臀丨亚洲性猛交xxxx丨av在线 亚洲 天堂

—— Dynamic
Current position: HomeNewsIndustry news
How should vitreous goods and true crystal identify
2021.11.23


The composition and structure of synthetic crystal and natural crystal are completely the same, especially when the crystal interior is very clean, can not see any characteristics, even laboratory identification has certain difficulties must use large instruments. In this case, it is difficult to distinguish natural crystals from synthetic crystals with the naked eye and portable instruments such as a ten-power magnifying glass. But there is also a less useful method, which is to test the crystal at room temperature until the temperature is stable with your hand to feel how cold it is. Generally speaking, natural crystal is cooler, and synthetic crystal or glass has warm feeling. However, this method is affected by the weather and environment, not applicable in winter. And because individual perception of temperature is different, it is only an auxiliary means of identification.

But the metropolis in most natural crystal exists or more or less contain content, it is the cotton that the expert often says, lock, cloud mist, mineral wrap a body to wait, form green ghost, of all kinds hair the variety such as crystal, send full of vitality. Synthetic crystals are cleaner, but sometimes have some characteristics. If one of the following characteristics appears, it can be determined as a synthetic crystal:

(1) a layer of dust will fall on the glass desktop if you do not wipe it for a period of time, which we must have seen. If you see what looks like "tabletop dust" inside a crystal, that means there are a lot of very fine gray or white dots along one plane or several parallel planes, and the rest of the crystal is very clean. So this is basically a synthetic crystal.

(2) Synthetic crystals sometimes have very thin hollow tubular inclusions. These hollow tubes are also basically parallel, sometimes reaching the surface, or they may be large and small, like nails. This is also only found in synthetic crystals, probably some flux residue from synthesis.

(3) Natural crystals are rarely green, or very rare. Such as green ghost, green hair crystals, and other varieties, the inclusion inside is green, but the crystal itself is colorless transparent. The crystal that appears on the market in great quantities of green transparency so, color is handled basically, and majority itself is synthetic crystal. Glass is cheap imitation, can come in a variety of colors, and sometimes can be made translucent, relatively easy to identify some.

主站蜘蛛池模板: 国模无码视频一区| 国产高清自产拍av在线| 两个奶头被吃高潮视频| 亚洲精品一品区二品区三品区| 久久久久无码中| 越猛烈欧美xx00动态图| 国产三级aⅴ在在线观看| 大地资源在线观看官网第三页| 猫咪www免费人成人入口| 人妻无码一区二区三区免费| 日本天天日噜噜噜| 特级a欧美做爰片第一次| 无码熟妇人妻av在线电影| 国产乱子轮xxx农村| 国产日韩欧美亚洲精品中字| 性xxxxx欧美极品少妇| 被拉到野外强要好爽黑人| 5个黑人躁我一个视频| 国产精品宾馆精品酒店| 99久久免费国产精品四虎| av无码av不卡一区二区| 激情综合婷婷丁香五月| 国产精品1区2区3区在线观看| 日本久久高清一区二区三区毛片| 日日碰狠狠躁久久躁9| 国产精品日韩欧美一区二区三区| 成年无码av片在线| 中文字幕久久久久人妻中出| 香蕉eeww99国产精选免费| 国产精品久久国产精品99 | 蜜芽久久人人超碰爱香蕉| 99视频精品国产免费观看| 无码人妻精品一区二区三区久久| 久久精品国产一区二区电影| 欧美激情一区二区三区在线| 精品麻豆一区二区三区乱码| 亚洲爆乳成av人在线视水卜| 亚洲丁香五月天缴情综合| 国产精品国产三级国产a| 国产性―交―乱―色―情人| 噜噜高清欧美内射短视频|