Opal is a micro-roastery and brew bar that roasts “seasonally rotating coffee roasted for clarity & character”. The roast is light and well developed, aimed at sweetness, clarity and brightness, and the coffees come through importers and producers chosen origin by origin, among them Mi Cafe Trading Co. and Omwani. Opal roasts every Monday and suggests resting its coffee for at least a week, with the flavour peaking around day 14 to 20. Its roast suits espresso or filter unless a coffee’s description says otherwise, and for espresso it recommends longer shots with a slightly shorter extraction time.

Rosta Coffee Bar, just outside the city walls, is Opal’s café: “Seasonal Coffee & Baked Goods”, with an Opal coffee on espresso, rotating batch brew and a pour-over menu, and the Opal retail range on its shelves. The bakes run from brown butter banana bread to cruffins, and a hand-painted coffee tree by Marty Green Art hangs in the shop.

Opal also sells wholesale and equipment to cafés, and runs cupping evenings of its current coffees. Its coffees sit on café shelves across the UK.

Coffee on the shelf

Photograph: Opal Coffee Roasters