What is the difference between glass nail files and crystal nail files?

Which ones are better?

Crystal has different definitions in different countries; the main criteria are the index of refraction and density, which are influenced by the composition of the glass. Crystal glass typically contains extra ingredients that enhance the reflection of light, making the glassware more brilliant. E.g.  lead crystal glass contains a higher volume of lead oxide; Bohemian crystal is the term for glass with an increased content of potassium oxide.

Glass files are made of flat float glass; they cannot be categorised as crystal. But, this is true for glass files from all manufacturers; no manufacturer makes them from crystal glass. Standard float glass is used for them, and float glass never has the same parameters as crystal glass.

Difference between crystal nail files and glass nail files

Briefly, the term ‘crystal nail files’ is very common and established on the market, so companies producing glass nail files present them as ‘crystal nail files’ too.  But from a technical point of view, this is simply the mixing of the terms glass and crystal.

How is a Czech glass nail file produced?