This International Standard givesThe classification of,and specifies requirements and test methods for, dental casting alloys with a noble metal content of at least 25%(mass fraction) up to but not including 75%(mass fraction).
EN ISO 8891:2000 history
2000EN ISO 8891:2000 Dental Casting Alloys with Noble Metal Content of at Least 25% but Less Than 75% ISO 8891:1998
1995EN ISO 8891:1995 Dental Casting Alloys with Noble Metal Content of 25% up to But Not Including 75% (ISO 8891: 1993)