Black silk Alex shirt from Katharine Hamnett London featuring a classic collar, a lightweight construction, a front button placket, front flap pockets, long sleeves, a loose fit and a curved hem. POSITIVELY CONSCIOUS: Katharine Hamnett scores 4 out 5 by independent ethical brand rating agency Good On You. It uses some eco-friendly materials and low impact non-toxic dyes in all of its products. It manufactures locally to reduce its carbon footprint and does not use fur, leather or exotic animal skin.