Prime leather skins have gained as much as 16 percent this year alone, according to Mulberry, spurring companies such as Chanel and Kering to buy tanneries to secure supply.Ballooning luxury prices come as the cost for all accessories, from fast-fashion purses to regular belts, grew at an average of less than 1 percent annually in Europe between 2005 and 2012, according to Eurostat, the statistica