From Chronoswiss, this architectural watch in steel opts for a regulator-style display, with separate indications for hours, on an openworked dial at 12 o’Clock, and minutes, shown by a central hand. Retrograde seconds are on a scale in the bottom portion of the main dial. Rated water-resistant to 100 metres, this watch truly stands out for its dial, which is constructed on two levels from 42 components. The base is hand-decorated with a captivating guilloché pattern under a chemical vapour deposition (CVD) coating that mimics the colours of the Brazilian Paraiba tourmaline (which also gives the watch its name), shifting in the light from turquoise to green, petrol blue or violet. A black galvanic treatment accentuates the rest of the dial furniture and bridges. This 50-piece limited edition retains two classic elements: an onion crown and a fluted caseband.