Given its name, you can’t be surprised that Fusion Cuisine gave us a bit of information about gem fusions to chew on—that should be no spoiler at all. It was definitely a novel kind of fusion, and it seems to have novel effects to go along with it. Opal and Sugilite gave us one set of expectations, and Alexandrite seems to challenge them.
Alexandrite differs from Opal and Sugilite in a couple of ways. Visually, she is designed very differently (though has a commonality with the temple statue that we’ll discuss). However she also acts very differently than either of the fusions we’ve seen previously.
The first thing a viewer notices when they see Alexandrite is the color palate. Opal and Sugilite both chose one of their component Gems’ colors to primarily use, with Opal mainly using Pearl’s coloration and Sugilite mainly using Amethyst’s. The result in both cases was a Gem who had her own color, much like all of the regular Gems we’ve seen so far. They seemed “normal”, though larger and more powerful.
Alexandrite, composed of three Gems, doesn’t choose one color to use. Instead she has three main colors, one representing each Gem who composes her. It looks very discordant, which will be very important when we get to how she acts.
Then there is the fact that she has two mouths. This is very much like the temple statue (presumed to be a fusion of Rose Quartz, Garnet, Amethyst, and Pearl given the placement of gems on it) which has two faces in addition to its many pairs of arms. Both Opal and Sugilite had extra arms, and Sugilite had extra eyes as well (which made sense because Garnet has an extra eye), but only Alexandrite and the temple fusion (both fusions of more than two Gems) have the extra mouth/face in common.
A side detail that’s very easy to miss because of the way the scenes are shot is potentially very important: all of the Crystal Gems, including Opal and Sugilite, had previously incorporated a five-point star into their designs. Alexandrite only uses a four-point star in hers.
Both Opal and Sugilite regarded themselves as individuals. “I don’t have it.” “I forgot how great it feels being me.” Every time they reference themselves they say “I” rather than “we”. Alexandrite is different. The Gems start arguing with one another (you can clearly tell it’s Garnet saying “cut it out you two!”) and fighting, using arms to hold others and even throwing a punch.
Rather than being a single entity, Alexandrite seems to feature all three of her component Gems as still-conscious actors. It’s possible that Opal and Sugilite are the same way, but the balance of evidence doesn’t favor that view. With Alexandrite it’s obvious that she’s not her own Gem the way that Amethyst, Garnet, or Pearl is, while Opal and Sugilite always act like they are and are usually spoken about like they are.
This is probably related to her being composed of more than two Gems, but since Steven doesn’t know much for sure about fusion we don’t know either.