The Princess of Wales always gives good hair, but this week, her chosen shade felt decidedly more autumnal against her wardrobe of forest greens and rich blues. While attending a series of engagements over the course of a three-day state visit from the Sultan of Oman, the Princess – who usually visits Chelsea’s Richard Ward salon for her hair colour – has unveiled more golden-toned lengths, with subtle waves adding to the glossy finish.

It’s a seasonally-appropriate hue that Siobhan Haug, a colour specialist and founder of Haug London Haus salon, predicts will come to reign supreme as we head into the colder months. She calls it “teak brunette”, inspired by the tones of teak tree timber in all of its honeyed, golden glory. “On hair, it translates into a medium-to-dark brown with golden, tawny undertones,” Haug previously told British , “and it moves from sun-warmed gold to a deeper, softer brown, much like teakwood itself as it matures.”

In fact, woody brunettes with soft, botanical undertones are currently among the most-requested colours at Haug. “There’s something sophisticated about shades like this thanks to the balance of depth, which highlights warm undertones without a trace of brassiness,” said Haug.

A more flaxen shade like Kate’s works best on those with a brunette base, adding warmth and dimension. With that in mind, Haug suggests requesting balayage, a freehand hair colouring technique that lightens strands without using foils, and looks a little more natural compared to traditional highlights. “Ask for honeyed tones that sit within two levels of your brunette base, as these will lend the richest, most natural-looking dimension without any harsh contrast,” said Haug.

The finishing touch should be a shine-enhancing hair gloss to blend the blonde tones seamlessly into the brunette strands. “And if you’re covering greys, a permanent tint combined with babylights, essentially thinner, more subtle highlights, builds the same multi-tonal base,” said Haug.