The second anchor in question is a Northill folding in stainless steel. Sadly, these are no longer made anymore, but if you ever come across one at a nautical flea market my advice is snap it up as they are one of the best anchors ever made!
The reason behind this is that the Northill folding was not actually designed for boats as such but instead were designed for the PBY flying boats where every ounce counted.
Being light at just a kiss over 12 pounds and the fact that they fold up but have holding power that matches most thirty-five pound anchors they do kind of rock. The icing on the cake, of course, is the fact that they are built of 316 stainless!
We mainly keep ours around as a kedge as being light, and it's folding action is tool-less (it just snaps open) so it is easy to deal with in a hurry and is dinghy friendly... What's not to love!