Spire gem cut question

[Leto85]

I am collecting gems (like I collect almost everything in game that can be collected) and once I've heard about spire cut gems, and how to get them I was starting to get one of every type of gem.
The problem is now that it is occacionally rare to get a spire cut. I believed it was a change of 20% so I have to save before I try and than get back to the main menu to start again when I got something else I didn't want. This way it could take a enourmous amount of time to get a spire.

Until now I have already created 7 different types of spire cut gems since yesterday, but I strugle with some 'species' that just doesn't see to be possible to get a spire cut from. Those are nodule and geode.

Before I try again I was hoping that someone can confirm me if it is even possible or not to get spire cut forms with the above named gem types or give a list with the gems that are capable of spireying (if that's a normal word).

Thanks in advance!

Oh and for incase someone don't know how to create a spire cut gem you need the following things: 3 spire cut tiberium (small) and 7 different heart form of the gem cut that you will get a spire cut out. The heart form need to be all from the same gem type.

[Saltypaws]

Your right, nodules and geodes you cannot do anything with, except split cut.  I don't usually keep them, unless you want to try something on the display case.  I always wondered what 8 of those would give you on the display case.   Maybe will have to try it.

[Leto85]

Your right, nodules and geodes you cannot do anything with, except split cut.  I don't usually keep them, unless you want to try something on the display case.  I always wondered what 8 of those would give you on the display case.   Maybe will have to try it.

A large split cut. I have one.

[samoht04]

The small tiberium spires will transmute on their own into large ones if you leave them on the floor or a stand 

[malteser60]

Your right, nodules and geodes you cannot do anything with, except split cut.

I also get heart shape cut as well as split cut with the geodes (and nodules I think, can't remember off the top of my head).

[Pam]

You can get split cut on geodes and nodules all the time.  Then you can get the heart cut on them when it becomes available.  Those are the only cuts for those two gems.

[Leto85]

You can get split cut on geodes and nodules all the time.  Then you can get the heart cut on them when it becomes available.  Those are the only cuts for those two gems.

Thanks, than I can quit trying.