What were the 16 Metals in MB1?

[Dor]

During Post Catacendre, 4 of the 16 Allomantic metals, namely Chromium, Nicrosil, Cadmium and Bendalloy, were unknown. Preservation swapped cadmium and bendalloy with atium and malatium, which means PC Scadrials should have been able to know abot 14 metals. However, in The Hero of Ages, PC Scadrials seem to be aware of 16 Allomantic Metals. Why is that?

[Ixthos]

1 hour ago, Dor said:

During Post Catacendre, 4 of the 16 Allomantic metals, namely Chromium, Nicrosil, Cadmium and Bendalloy, were unknown. Preservation swapped cadmium and bendalloy with atium and malatium, which means PC Scadrials should have been able to know abot 14 metals. However, in The Hero of Ages, PC Scadrials seem to be aware of 16 Allomantic Metals. Why is that?

They know there would be 16 metals, but not what all those metals were. 16 was seen as a significant number, and so even though they only knew of 10 for most, and aluminium by the obligators, the obligators didn't know the other metals, only that they would exist.

[Raphaborn]

8 hours ago, Dor said:

During Post Catacendre, 4 of the 16 Allomantic metals, namely Chromium, Nicrosil, Cadmium and Bendalloy, were unknown. Preservation swapped cadmium and bendalloy with atium and malatium, which means PC Scadrials should have been able to know abot 14 metals. However, in The Hero of Ages, PC Scadrials seem to be aware of 16 Allomantic Metals. Why is that?

They knew that only 16 metals made sense. 4 Physicals. 4 Mentals. 4 Temporals. 4 Enhancements.
Only they thought that the other 2 temporal metals were Atium and Malatium, and knew that there must be two hidden Enhancements. 
Perhaps those who knew how the Mistborns were born would think that Lerasium, and the alloy, were these two in hiding. Which makes sense, but obviously wrong.