Recipes for persuading concrete & hypertufa to take on an appearance of age vary. The best one that I've found is - just stand the casting in dense shade, under a male Holly tree. The Holly drops lots of pollen. Rocks, concrete footpaths and hypertufa (this lantern's hypertufa) don't take long to start going green. The lantern's been sitting there for about a year. It looks even greener in the picture because we've had drizzle all morning.

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