It depends. I am not up on this fictional material. But, I am guessing that your adamatium could be shattered or cleaved just like diamond.
For instance, concrete is very strong in compression (pushing together) but weak in tension (pulling apart). Diamonds are very strong under a uniform force, but they will shatter under an impact force. Aluminum is strong and light though once a defect forms, it is more likely to break.
Maybe if you describe the attributes of adamantium someone could make an analogy.