Can anyone identify this type of green tea? My house mate brought back from green tea from either China or Malaysia that was dark green balls that unrolled to large, thick leaves when steeped and I'm struggling to find anything similar!

It didn't have the same young/grassy taste like some of the jasmine tea I've had and instead tasted quite earthy and ... green! (Sound stupid I know)

Does anyone have any pointers to what I should be looking for? When I've searched for whole leaf green tea it comes back with Jasmine Pearls which are a lot longer and thinner when steeped but these were more substantial
In general, your description - dark green balls which unroll to full tea leaves, sounds like some variety of gunpowder green tea.  It is a quite common Chinese technique, as I recall.  Each pellet (also sometimes called "pearls") is a rolled and dried tea leaf, which unfurls when steeped. 

However, it is difficult to get more specific than that without more information.  There are several types of green tea that can be rolled into "gunpowder" form, with differing grades of tea, amount of aging, and years or growing locations (given growing conditions) all contributing to somewhat different flavor profiles.  You might be able to use the terms and look to see how the information about which varieties of gunpowder green match your house mate's tea or your experiences (or your own preferences) - but without more knowledge I don't know how to pin down the same kind of tea.