Blue Memory

An interesting study. You should have credit for trying such a tricky subject, especially without any interesting background or surrounding to reflect in the ice. As a test study it's fine, but critiquing it as a full image I don't feel this really hits home - but it's getting there (you yourself mention the element placement in your caption, so won't go into that).

If focusing on the large icicle for the moment: The cracks can indeed run this way, but what should be seen is the interfaces between tiny gaps, not the gaps themselves, as it is I get more of a carrot-y feel from them. I think working with sharper and more stark hilights would make this more icy. One could then motivate angled break surfaces to reflect more. Whereas this rather dull lighting could motivate a very limited palette, I would think this would live up a lot more if you added more colours to the icicle(s); with even limited light they really contain many more colours of the rainbow than one might think.

Introducing a more interesting background and source of light would make it easier to show the reflectiveness of this transparent medium while allowing to introduce hard darks in the ice. That might then also lend some purpose to the image beyond the pure ice-study test that it is currently.

Just my opinions, obviously! <img src="e.deviantart.net/emoticons/s/s…" width="15" height="15" alt="" title=" (Smile)"/> I hope I don't discourage you here, this is a very hard subject to get right, requires a few tries I imagine. If you don't already, looking at references is probably a must to get all the subtleties of frozen water.
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Griatch