How is this done? I mean, I know the High Lords of Terra must deliberate for ages before all being in agreement, but what would they actually deliberate over? Why and when would they decide to create a new chapter?
Also, the business is done on Mars by genetors, but how do they do it - what's the exact process, and how long would it take?
Do they take genes from any marines, or would it have to be the chapter masters, dreadnoughts or someone old enough?
And can genes be taken from any chapter, ie a recent one, or must they come from original first founding stock?