Quality Control Standard 7A Elements for ICP Certified Reference Material, 1000 mg/L K, 500 mg/L Si, 100 mg/L each of Al, B, Ba,

Quality Control Standard 7A Elements for ICP Certified Reference Material, 1000 mg/L K, 500 mg/L Si, 100 mg/L each of Al, B, Ba, Na, 50 mg/L Ag in HNO₃ 5%