Potash soda lead glass

The colours of the analyzed glasses were turquoise blue (14 samples), royal blue (12 samples), white (45 samples), red (135 samples), black (52 samples), colourless (21 samples) and gold (11 samples). Table I lists the samples by colour, shape, and form. The gold coloured beads were made from leaded glasses. All of the other samples were soda-lime-silica glasses, with variable amounts of potash. The complete data set is available from the authors. 

As a coloring oxide in lead potash glasses, manganese produces an amethyst color, while in soda glass a reddish-violet is produced. 

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