Alexandrite is one of the largest fusions; along with the equally gigantic Sugilite. She is one of the largest and tallest characters seen so far. She has pinkish red skin and six arms. Her eyes are covered by a dark visor, and instead of a third eye, like Garnet, or her fusion Sugilite, she has an alexandrite gemstone, representing the location of Pearl's gemstone, with three dark, oval-shaped shaped bubble lenses surrounding it. Alexandrite's primary face also functions as a mask, covering a second monstrous looking mouth beneath it.
Alexandrite's turquoise/bright teal star-shaped hair resembles all of the Gems hair styles. The length and wildness of her hair resembles Amethyst's, while the top of her hair styled to a point represents that of Pearl's, and the slight square shape where the styled point protrudes resembles Garnet's.
Alexandrite's attire represents a mix of all 3 Gems' clothing: The greenish gray leggings with a four pointed star cut out in each legging, resembling Amethyst's, the shoes and black shoulder sleeves are Garnet's, and the tunic is Pearl's. The gloves on each pair of arms are also the color of the skin tone of each Gem (Purple middle pair of arms is for Amethyst, turquoise upper pair of arms is for Pearl, red fingerless gloves on lower pair of arms is for Garnet). Curiously, when the Gems started to fight, when can see that Garnet can control the upper pair of arms, Amethyst the middle one, and Pearl the lower one.
Most fusion gems have a unique personality that is a rough combination of all the different attributes from the contributing Gems' disposition. Alexandrite starts off cold, intense, and messy, but as the fusion slowly starts to fail, the Crystal Gems' individual personalities become more prominent.
It is believed that like all Gems, Alexandrite can shapeshift, summon a weapon, and retreat to her gemstones. Being a fusion between four gems, Alexandrite is much more powerful. Alexandrite runs at extreme speeds. Furthermore, she has enough strength to lift heavy objects, like a bus, with ease.
- She is the most complex fusion seen thus far; involving the fusion of a total of four Gems (including Ruby and Sapphire).
- Ben Levin stated that, in theory, Alexandrite is taller due to being composed of four gems. 
- Alexandrite is the first, and so far only, four-Gem fusion shown on the show.
- She is the fifth fusion to be shown overall.
- She also has the most arms out of any known fusion. (Tied with Malachite, if you count all of her limbs as arms).
- Alexandrite's face can function as a mask, with the first face covering a monstrous looking mouth.
- The lower/second mouth seems to be mostly controlled by Amethyst.
- Alexandrite's appearance resembles the design of the Crystal Temple.
- However, the Crystal Temple fusion requires Rose/Steven.
- The "face mask" concept resembles the Crystal Temple, as the Crystal Temple is shown having 2 faces (the first being the mask on it's forehead).
- Alexandrite's eyes have not been revealed, however it seems likely that she has at least five: Two under the visor and three under the three lenses surrounding her forehead gem.
- Unlike Opal and Sugilite, and similar to Stevonnie and Malachite, all of the personalities from Garnet, Amethyst, and Pearl were portrayed within this fusion.
- When Alexandrite unfused, a still frame of animation shows silhouettes of Ruby and Sapphire where Garnet would have been.
- Alexandrite is seen in Attack the Light, as a special attack dealing around 7 damage-heavy strikes to all opponents on the field. She is the hardest attack to use in the game, as she needs 9 star points and for Garnet, Amethyst, and Pearl to all be at full harmony.
- A glimpse of her fusion dance is shown during this process.
- Alexandrite is the only Crystal Gem that has four-pointed stars on her outfit.
- At one point in "Fusion Cuisine", Alexandrite's hands are positioned incorrectly, with the gems of Garnet suddenly on Pearl's hands.
Learn more about the alexandrite gemstone here.
- Alexandrite is a rare color change and chromium-bearing variety of chrysoberyl.
- It is said that alexandrite was named after a Russian tsar named Alexander the second.
- Alexandrite is the birthstone for June along with pearl and moonstone, and whoever wears alexandrite will reap the many benefits and astrological powers it possesses.
- Alexandrite is a stone that is associated with discipline and self-control.
- Alexandrite is also a gem for the 55th wedding anniversary.
- The color change phenomenon seen in alexandrite is referred to as the 'alexandrite effect'. The change in color can be observed under certain lighting conditions, typically under daylight and incandescent lighting.
- The alexandrite gemstone is green when in the presence of light composed mainly of greens and blues (e.g. natural light) and red in the presence of light composed mostly of reds and yellows (e.g. incandescent light), and purple when shown under both sources of light.
|Pearl's gemstone on Alexandrite appears to be smooth without a facet, but does have a ring around the middle.||"Fusion Cuisine"|
|Amethyst's gemstone on Alexandrite has a hexagonal facet. It is a tetradecahedron.|
|Ruby's gemstone on Alexandrite has a square facet. It is a decahedron.|
|Sapphire's gemstone on Alexandrite has a triangular facet. It is an octahedron.|