National flags might seem like a riot of colour, but there is one colour that you will almost never see on a flag and the reason comes down to the ancient trade in rare sea snails.National flags might seem like a riot of colour, but there is one colour that you will almost never see on a flag and the reason comes down to the ancient trade in rare sea snails. National flags might seem like a riot of colour, but there is one colour that you will almost never see on a flag and the reason comes down to the ancient trade in rare sea snails. Science & tech Articles | Mail Online
Revealed: The surprising reason why almost no national flags feature the colour purple
