Cruxite

Cruxite is a crystalline substance found in Homestuck that comes in numerous different colors. It is primarily found in the form of dowels used for alchemy; however, the artifacts used to facilitate a player's entry to the Medium are also composed of cruxite.

Dowels
Cruxite dowels are long cylinders extracted from the Cruxtruder, first seen HS 2080 (here). They can be used in conjunction with the Alchemiter to create special objects, and can be carved by the Totem Lathe to change what kind of item is created. A carved cruxite dowel was used to create a cruxite artifact for each of the kids. Its extraction released the Kernelsprite and began the countdown towards the meteor impact. Many dowels can be extracted, but only the first dowel releases the Kernelsprite and initiates the countdown.

The color of the cruxite seen so far corresponds to a player's associated color: Gray for Karkat Vantas, mustard for Sollux Captor, and brown for Tavros Nitram. The colors have been swapped between the pre- and post-scratch kids in respect to their typing colors: cyan for John Egbert, blue for Jane Crocker, magenta for Rose Lalonde, lavender for Roxy Lalonde, vermilion for Dave Strider, red for Dirk Strider, green for Jade Harley, bright green for Jake English.

Kanaya and Eridan are shown making a HS 4946 (wand) with black cruxite. This was most likely cruxite found in the veil and unrelated to a specific player.

Artifacts
A cruxite artifact must be created by a Sburb player in order to enter the Medium in a game of Sburb. It is alchemized from the pre-punched card that is provided at the beginning of the game. Like their name suggests, they appear to be made of pure cruxite. Each artifact is unique to the player in question, and most of them have been "used" by breaking them in some fashion. A much larger version of this item is brought to earth by the meteor headed for the player's location. In the future, the Exiles will find and use these to contact their players.

Artifacts are not alchemized like other items: Instead of the item simply appearing, the artifact is usually dropped by a larger item, which then disappears.

Andrew, each cruxite item is symbolic of departure.

Cruxite Apple
A mysterious blue apple created by the Alchemiter while using a carved cruxite dowel. The apple came from a tree which the said device created. Biting this apple saved John from being obliterated by a meteor by transporting him and his house into the Medium. The apple is not in John's inventory, so it is safe to assume it dissolved after it was used. The design of the Helipod Base is based on it (which is also why it's grown out of a tree). The Cruxite Apple's captcha code is cZCMY4Qf (derived from the hole pattern on the card HS 2081 (here)).

The apple symbolizes the loss of innocence, as it derives from the biblical tale of original sin; in which Eve eats the apple from the tree of knowledge of good and evil. It is notable that knowledge and deep thought are said to have a link with air, which is John's associated classical element. Another interpretation is that apples are harvested in Autumn, the windiest of all the seasons, which is also a link to wind.

Cruxite Bottle
A mysterious purple bottle came from a cabinet created by the Alchemiter while using a carved cruxite dowel. The bottle was almost lost when it was knocked into the river by Zazzerpan's hand. Rose leapt over the waterfall to save it, before being rescued by Jaspersprite. Breaking this bottle saved Rose from being obliterated by a meteor by transporting her and her house into the Medium. The bottle is not in Rose's inventory, so it is safe to assume it dissolved or disappeared after it was used. The Skyship Base that appears in the future forms the "cork" on a larger bottle-shaped structure mostly buried underground where Rose's house once stood.

The bottle symbolizes a leap of faith, trusting a friend. The fact that there is wine inside the bottle leads one to think of Rose's associated classical element being water and her mother's alleged alcoholism. Breaking a wine bottle is also a symbol of christening a new sea vessel. Bottles are also made of glass, which comes from sand at the beach. This could also be a reference to Rose's associated classical element.

The cabinet also resembles Roxy's fetch modus.

Rose's entry process ties into her Aspect, Light, being associated with information and knowledge: she had to go through quite the logistical process in order to enter.

Cruxite Crow's Egg
Dave's pre-punched card to facilitate his entrance to the Medium contains a cruxite egg-shaped item. Dave's card produces a large crow which lays an egg and then disappears.

Dave's Crowsprite stole the Egg and took it to a nest made of shitty swords and soft puppet ass in an attempt to hatch it. Though he initially decided to let the Sprite try to hatch it, as time ran short Dave was forced to climb the tower to the nest. He was attacked by his Kernelsprite and knocked off the tower, but luckily Dave's Bro was around to send Dave his rocketboard and slice the oncoming meteor in two. This outrageously awesome act bought Dave the precious few seconds he needed for the egg to heat up and crack, sending him into the Medium.

The 'eggy loking thign [sic]' that Rose reads about is another cruxite artifact of this type. The item is related to the Eggy-Looking Base that has appeared in the Future.

The crow's egg symbolizes a lesson in patience (which ties into his Aspect, Time), as Dave has to wait for the egg to hatch. An egg can also symbolize a barrier and protection, as well as overprotection. The egg hatching can mean finding independence, or coming out from someone else's shadow (similar to how Dave must become independent from his Bro). The only way the egg has a bearing on Dave's associated classical element being fire is that to hatch an egg the mother must sit on top of it for warmth. The fact that the egg needed warmth and time in order to hatch is probably a reference to Dave's planet, the Land of Heat and Clockwork.

Cruxite Dog Piñata
A green piñata shaped like Becquerel was used for Jade's entry into the Medium. She was blindfolded when this item appeared and attempted to smack it with her rifle. When she did land a blow, the piñata seemed to propel her out of the tower, probably using First Guardian powers, because it still has the shift animation. She eventually shot it through a portal created by Becsprite. The Cruxite Piñata's captcha code is q84a0HAC (derived from the hole pattern on the card HS 4805 (here)).

The dog piñata and its method of destruction symbolizes a shot in the dark, killing a friend for its own good, and/or the greater good. How this ties into Jade's associated element being Earth is unknown, but perhaps may be as simple as the tree the piñata must hang from in order to use it. Alternatively, in Mayan culture, dogs symbolize both death and renewal, being guides in the underworld. This may tie Bec's role as Guardian with burial in the earth. Also, when piñatas are broken, candy and other treats fall to the earth. Piñatas are also made out of papier mache, paper and glue coming from earthly sources (plants and animals).

Jade's entry process tied into her Aspect, Space, in that she was moving frequently through space during the HS 4827 (whole ordeal.)

Cruxite Tree
Jane's pre-punched card contained a tree, which means that the tree itself is the cruxite artifact. It is quite an oddity among the others.

Unlike the other cruxite artifacts, it did not come from a bigger item, and Jane was confused as to how she was meant to interact with it. Given the lack of detail surrounding her entering, one might guess that AR was using a walkthrough to set up the game, as Rose had, or perhaps (as a computer) just knew how the game worked.

Another crucial difference is that Jane was apparently not meant to interact with it, as her pre-scratch counterpart did. After a few moments, the tree simply vanished, taking Jane into the medium.

It is also theorized that the tree, lacking the fruit that John's had, was meant to be symbolic of the session being void, as the tree "bore no fruit". It is also speculated that Jane was supposed to wait for the tree to grow, given that she is the Maid of Life. The tree may also be a reference to how the post-scratch kids had no biological parents.

A possible theory is that the tree bore no fruit due to Jane not putting an object into her sprite, unlike her counter-part.

Cruxite Cherub
This is Jake English's cruxite artifact. The totem matches the shape of Jane, John, and Jade's. Much like Jade's, his artifact is hanging from a tree in a piñata-like fashion. However, his appears to be hanging from a noose, similar in a way to 's effigies. The fact that it resembles a cherub makes further ties between Jake and and may reference how Aranea believes Jake will defeat him. Interestingly, it is the first cruxite artifact shown which has an outlying color on it, being the red cheek marks, like Caliborn's once he had dominated.

Trolls' Artifacts
The trolls' cruxite artifacts were never shown during Hivebent. However, we know that they matched their typing color, as we saw cruxite dowels and cruxite totems of several trolls. From the shape of the exile bases, one could assume that Karkat's was a crabby-looking thing with six legs, while Kanaya's was the skull of a Mother Grub. This could suggest a connection to each troll players' Lusus/Guardian. Another fact to support this theory would be Jade's artifact being shaped like Becquerel. However, Andrew Hussie stated that the trolls' artifacts were deliberately left to the reader's imagination, so this might not be indicative at all.

Trivia

 * The Salamanders of the Land of Wind and Shade think cruxite is very useless.
 * Jade, John, Jane, and Jake all had the same shape of cruxite artifact, which all produced trees. Whether this is significant, or whether Hussie simply became tired of making different shaped cruxite totems, remains to be seen. It could be indicative of Dirk and Roxy's artifacts; as their totems share the same shape, they may also have trees as their artifacts.
 * Although the entry processes for Roxy and Dirk's houses were shown, neither appeared to have a cruxite artifact. Whether this is due to Squarewave and Sawtooth facilitating the entries remains unclear.
 * Jade, John, Jane, and Jake's cruxite artifacts shape may also be a reference to their family tree, especially with John's apple representing his status as Jane's son.