Partitioning A Drive For Encryption

I want to create a small partition on my 1 Tb drive (Mac Book Pro Intel) and then encrypt it for the storage of various encyption and other drive recovery keys.

Using disk utilities I am given a choice between partition or volume. What ever I choose it would be small maybe 10 Gb. Not sure which to pick. What would be approriate and what are the gotcha's when picking either volume or partition.

Cheers

Pete