MacThorstenson

Just now, I think I am here. said:

Doesn't Harmony disapprove of Hemalurgy though?

You're right. But I just had an epiphany, Kelsier held the shard of preservation for a while, and thus would know what his godmetal did, no? I think that he wouldn't know about the rest of the metals instinctively, but he would know about what his metal did.

23 hours ago, I think I am here. said:

So then how would they know what lerasium does? Seems odd that they're not sure about chromium but are sure in lerasium, a god metal which is only available in a few small beads which have probably been removed with the remaking of the world.

My guess is that they may have had a little help from harmony in filling out this table.