The story. The classic four: where we met, our first home, where we said yes, where we live now. Or where each of you was born and the two places you've lived together. Or the four homes of one long life, for the parents. The captions are yours to write.
How it is made. Every coaster is drawn from OpenStreetMap around the spot you pick: 300, 500 or 900 metres across. The slab is 3.5 mm; the whole map stands 1.2 mm above it. Water is the lowest step, then parks, then streets, and the buildings are flat pads at the very top — the same height as the rim and the caption letters — so a glass rests on buildings and rim together and never rocks. A dot at the centre marks the exact spot. Printed in up to six colours in one go; the palette sets them all.
Sizes. 95 mm across (3¾ in), 4.7 mm thick. One coaster $12; the set of four $38.