How to Identify the Production Year of Glass?
1 Answers
It is represented by numbers + dots. Dots before the number indicate the first half of the year, calculated by subtracting the number of dots from 7. Dots after the number indicate the second half of the year, calculated by subtracting the number of dots from 13. The number represents the year, small dots represent the quarter (up to 4 small dots), and large dots represent the corresponding month within that quarter. The number indicates the production year of the glass. The small dots in the first row represent the month of that year, and the second row represents the corresponding day of the month.