Glassworking is the winning of vessels and panes out of a substance that is only workable while it is dangerously hot and unforgiving the moment it is not. Bottles, flasks, phials, goblets, beads, window quarries and — for the very few with the patience and the ground stone — lenses.

Glass phials are also the vessel of choice for anything that must be seen without being opened, and a thin-walled jar is the standard body of a fire pot — which is a use the maker is rarely told about.

Crafting

Glass is made by the common crafting routine — workshop, expense, test, result, masterwork rolls, repair. What follows is what is particular to the glasshouse.

Expense. Reckon one day per 6d of the item’s sale price, at a material cost of 2½d per day.

Test. A Glassworking Success Value test, read on the standard ladder. What it fixes is clarity, freedom from bubble and streak, and evenness of wall.

Glazing is sold and worked by the square foot rather than as an article, and is the bulk of a town glazier’s trade — a cathedral window is reckoned in hundreds of feet and years of work.