There's gold, the color option, and gold, the precious metal. Truly Exquisite means the latter when it talks about its 24K Gold Samsung Galaxy S8 and Galaxy S8+. There's also 18K Rose Gold and, for a more neutral color, a Platinum option. You can combo those noble metals with the Midnight Black or Orchid Grey colors from Samsung as those determine the color of the glass back - Truly Exquisite only gilds the metal frame, while the front is Black on all S8 color options. Anyway, you're getting more than just a gilded phone for your £2,250 (without VAT) - yes, that's how much they cost....
Source: http://www.gsmarena.com/truly_exquisite_flaunts_galaxy_s8_and_s8_covered_with_24k_gold-news-24476.php