Constellation and Mythology
The Caelum constellation is based on a sculptor's chisel, and is the eigth smallest constellation in the night sky.
Although there is currently no known myth associated with this constellation, it may have been influenced by the myth of Pygmalion, a sculptor of Cyprus. Unsatisfied with women, he began working on a statue of the ideal human female. However, his skill is so great, the finished sculpture looks unimaginably beautiful and realistic, and Pygmalion falls in love with it. Knowing his love is doomed, he prays to Aphrodite to allow him to meet someone like his statue, but the goddess pities him and, when he returns home and kisses the sculpture, she brings it to life so he can marry his ideal woman.
Another story that could be linked to the constellation is the Asian folktale of the Stonecutter. A lowly stonecutter chips blocks of rock from a mountain with a chisel every day for a living until, one day, he happens to see a prince and his entourage go by. He wishes he could live a luxurious lifestyle like the prince and, that night, his wish is heard and granted by the spirit of the mountain, who has noticed the Stonecutter's hard work.
The stonecutter becomes a wealthy prince but becomes angered one day to find his lovely garden flowers withering under the hot sun. Noting its power, the Prince wishes to become the sun, and does through the mountain spirit. As the Sun, he begins scorching and burning up all the land, until he is covered by a rain cloud. The Sun wishes to be the cloud next, and becomes so. He floods the lands and causes horrible thunderstorms; everything is washed away except the mountain. Furious, the Cloud wishes to become the mountain, and the spirit, granting his wish, departs forever.
Now the new mountain spirit, he is finally pleased with his power, until one day he feels a sharp sting: it is another lowly stonecutter, chiping away the rock with his chisel. The sharp pain caused by the chisel causes the new Spirit to tremble in fear.
Created by the alchemists of Mu along with the other 87 Cloths. During the Black Saints arc Dragon Shiryu ventured to Aries Mu in Jamir to get his Dragon and the Pegasus Cloths repaired. While there Mu used the tools to repair the two Bronze Cloths. If those tools belong to the Caelum Cloth or if there is another set of tools for the other repair Cloth, Sculptor, is not clear. The tools, however, came to appear again after the Sanctuary arc when the Bronze Cloths needed repairs again.
In the Saint Seiya Taizen we can read that the Graad foundation restored the Caelum cloth sometime, most likely after Hades' defeat. It was listed as coming from the Cloth Graveyard in Jamir and got its properties researched.
The cloth has accompanying tools that can be used to repair other cloths. Which would be handy on the battlefield if someone needed quick repairs. It shares these properties with the Sculptor Cloth. The tools have been seen in the possession of Aries Mu in Jamir, and after the Caelum Cloth was repaired it was most likely returned to Mu's apprentice Kiki or any other descendants of Mu.
In total 7 tools belonging to the cloth has been shown. A hammer, two different chisels, tongs, a drill, a scriber, and an unknown tool.