Mistborn/Fridge

Fridge Brilliance: In book two we are introduced to the allomantic alloy Duralumin which is obtained through an alloy of Alluminum and 4% copper, and it is mentioned that the aluminum comes from a recovered noble's silverware this may seem to be an odd metal to make silverware out of until you realize that allomancers can absorb trace amounts of metals through normal eating, and that aluminum causes all of a allomancers metal reserves to be drained. This means that it is a defense feature, you give your enemies (i.e. everyone else) the aluminum silverware in an effort to depower any would be allomantic assassins
- No. Aluminium still needs to be deliberately burned to drain an Allomancers metal reserves. The silverware was likely made of aluminium because in pre-industrial settings aluminium was priceless, and possession of aluminium plates and cutlery was a status symbol. e.g. Napoleon had a aluminium dinner set which he only used for his most important guests, less distinguished visitors had to make do with gold implements.
- Furthermore, the use of Aluminium was a secret the Lord Ruler kept for himself.
- Frige Brilliance comes about when it's been said that aluminium can't be pushed or pulled, so not only is it super expensive, but it's also less likely to be used by a coinshot assassin to kill you from a distance.

A meta-example: in the short story "The Hope Of Elantris", to be found in Sanderson website, it is mentioned that the Aon "Ati" means "Hope". Ruin's original name was apparently Ati, hence atium. So not only is Ruin likely originally from Elantris, we also get the gag that RUIN was originally named HOPE.
- Jossed, unfortunately.^[1]

In Hero of Ages, Vin, not knowing the name of the malignant entity she inadvertantly freed, starts calling him "Ruin" because it just seems to fit. This is, of course, said entity's acual name. Was it just Vin making a lucky guess? Nope; we find out later that Ruin actually rather likes Vin because of how deadly she is, and he can speak into her mind via her earring and be subtle enough she can't tell it from her own thoughts (or her memories of Reen). She knows his name because he told her.

At first I was confused as to why guards in a pseudo-medieval/renaissance-tech setting only wear breastplates instead of full mail, helms, greaves, and so on. Even with the obvious threat of Allomancers and Mistborn, if you're going to armor up against mundane threats, you'll want full protection. Then I realized that if you're just wearing a breastplate and an Allomancer shows up, all you need to do is cut the straps and you're no longer immediately helpless against an Allomancer, while a fully-armored soldier will never get all his gear off before an Allomancer uses him for all manner of hilarity. Going around with just a breastplate is an effective compromise between being armed for mundane threats and still being of some utility against an Allomancer.

I just realized why Allomancy shatters the crystals in the Pits of Hathsin: Allomancy is the power of Preservation, and the crystals in the Pits gather the body of Ruin, so the powers are diametrically opposed. Allomancy would naturally disrupt Ruin's power. Preservation probably deliberately set that whole thing up.