Quote:
The metals that form the most valuable alloys with steel are silver, platina {platinum}, rhodium, iridium and osmium, and palladium; all of these have now been made in the large way, except indeed the last named. Palladium has, for very obvious reasons, been used but sparingly; four pounds of steel with 1 to 100 part of palladium, has, however been fused at once, and the compound is truly valuable, more especially for making instruments that require perfect smoothness of edge.
The fact that they specifically mention the use of iridium and osmium together strongly suggests that's exactly what you have.