Glass Koubou no Renkinjutsushi

Luo is reincarnated as the eldest son of a frontier lord's family. After meeting the fire spirit Lava, he is reminded of his dream from his previous life of becoming a glass artist. He wants to create beautiful glass art with his own hands once again. When he finds out that glass is not widely used, he challenges himself to create glass with the power of alchemy together with Lava. Together with his renowned alchemist master, he creates potions, beer glasses, and the first glass mirror in another world. Source: MU