Massive" sounds very big just considering the dictionary descrition:

- of considerable magnitude

- homogeneous in structure, without stratification, foliation etc

- occuring in thick beds, without minor joints and lamination, said of some laminated rocks

- Mineralogy, irregular in form though occasionally crystalline in internal structure

Wikipedia

- In Mineralogy, shape & size give rise to descriptive terms applied to the typical appearance or habit of crystals.

- The many terms used by mineralogists to describe chrystal habits are useful in communicating what specimens of a particular mineral often look like.

- the development of a particular habit is determined by the details of the conditions during the mineral formation/crystal growth

- Massive or compact crystal habit...Shapeless, no distinctive external chrystal shape

Example ...Serpentine

I often wondered what they meant by Massive. Perhaps Hoov or someone else can expand on the above.

SN