london-based firm has unveiled its luxury brand of apple watches .
the expensive devices are made with 24 karat gold , rose gold or platinum .
others are encrusted with diamonds and have python or crocodile skin .
prices range from a ` modest ' £ 2,000 -lrb- $ 3,000 -rrb- to £ 120,000 -lrb- $ 177,000 -rrb- .