<p>It is not a stretch of the imagination to see it either way. I think it is the mind gem and just wanted to be reconnected to the cube. Their power is not the same, but very similar.
</p><p>I find it funny that the stones/gems give off gamma readings because the Hulk is already powered by gamma radiation. If Loki's goal while in SHIELD captivity was to unleash the Hulk, the scepter could have brought about a transformation without getting him angry, or maybe if it was the mind gem triggering the Hulk-portion of Banner's brain thereby triggering a transformation anyway.
</p><p>In any case, the scepter and cube are linked in power readings, each a singularity from the beginning of the universe wanting to rejoin with the rest of the 5 stones, like the One Ring in Tolkien mythology. The only reason they are not drawn together is because they are contained in some sort of cosmic containment unit (a la Infinity War storyline). The scepter holds the mind gem's power in check the same way the tesseract holds the reality gem's power back. The granite block for the aether and the orb worked the same way.
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