Why A Nice Crystal Cup Generally Can Not Be A Drinking Cup?
Why a nice crystal cup generally can not be a drinking cup?Because they are basically made of lead glass.
There are two kinds of crystal glasses on the market: natural crystal glasses and artificial crystal glasses. The natural crystal glass is composed of silicon dioxide, which does not contain or contains very low lead content. It is generally a high-grade product. This kind of crystal glass is very expensive. The common crystal glasses on the market are basically made of artificial crystal. They are cheap, but the content of lead oxide is as high as 24%. Such lead will be released slowly.When the lead in the blood accumulates to a certain concentration, it will lead to the decline of human memory and intelligence, mental disorders, nightmares, insomnia and other symptoms.
In order to make the cup look good, merchants usually make the cup into various colors.There are also two processing methods:1.Add various metal oxides,though some metal oxides are harmful,but the temperature of boiling water is 100℃，such temperatures do not yet constitute the decomposition of these oxides.Another way is to paint the surface. These colors will contain a lot of harmful substances, mostly lead and chromium. Chromium can cause cancer and is associated with osteoporosis and serious kidney problems. It is difficult to judge from the appearance whether it is external dyeing or adding color when making.We can only try to choose brand cups and those with obvious ingredients.
A beautiful crystal cup is usually beautifully carved so it can attract more users to buy.In order to look clear and transparent and facilitate cutting, this cup is added with a lot of lead oxide.
Then,how can we choose a glass cup for drinking glass cup?
1.Try to choose high borosilicate glass with simple shape.
High borosilicate glasses are very safe because the cost of making them is not very high. There are also high priced hand-made high borosilicate glasses with colors and patterns,but the price is very high.
2.Try to choose transparent glass cup,do not choose colored cups, especially gradient colored cups,most gradient colors are surface staining.
3.Choose a light glass instead of a heavy carved glass.
Heavy cups are usually made with lead, and the knocking sound is also very dull. After adding lead, the hardness of the glass is low, so it is easy to carve. The light high borosilicate is thinner and harder.
When buying, we can simply tap the glass gently. The sound of high borosilicate glass is often clear, while the sound of lead glass is thick and dull.