One of my fav picks ever was a huffschmidt granite pick. However, i wore it out fast ( i could resharpen i suppose). It was around 10 mm or so. https://www.plectrum.ch/product/limited-edition-very-rare-pattern-10mm-galalith-granite-plectrumI have a ton of his picks, but the one i use still is the 3mm brass. It is the hardest pick he makes. It is really good. The only complaint is alt picking if you pick fat, you will hit the raised textured part. https://www.plectrum.ch/product/hufschmid_brass_plectrum_pickThe picks that i use besides that brass one now are attak picks https://attakpik.com/products/stealth-2-0i have several styles, and i am always wishing for a size bigger than attack and smaller than xl, but the small one has some serious fucking attack. When i am going for the tightest palm mutes, this is the one I use.