wine bottles

Why Do Coffee Lids Have Two Holes?

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A sealed lid could easily melt from the steam created by scalding-hot coffee. However, the drinking hole and the second, tiny hole both allow steam to escape to keep the lid from melting Why are there two holes in a coffee cup? What is the purpose of the second hole in the coffee cup lid? … Read more

How Do You Make Blue Bottles At Home?

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Small concentrations of cobalt (0.025 to 0.1%) yield blue glass The best results are achieved when using glass containing potash. Very small amounts can be used for decolorizing. 2 to 3% of copper oxide produces a turquoise color. How do you make glass blue? Small concentrations of cobalt (0.025 to 0.1%) yield blue glass The … Read more