Blue Stained Glass is a dyed variant of the glass block, made by placing one blue dye in the center of the 3×3 crafting grid and eight glass blocks in every other cell — the recipe yields eight Blue Stained Glass blocks. Blue dye crafts from lapis lazuli or a cornflower, and glass smelts from sand or red sand, so lapis lazuli plus sand covers the entire recipe chain. Blue Stained Glass breaks at the same speed with every tool, because stained glass has no assigned tool, and drops itself only under a Silk Touch enchantment (a tool enchantment that makes delicate blocks drop intact); without Silk Touch, breaking stained glass yields nothing. Blue Stained Glass stacks to 64, emits no light, never catches fire, and never appears in world generation — only magenta, brown, black, light gray, and white stained glass generates naturally.

In builds, Blue Stained Glass delivers color that clear glass cannot: blue skylights, church windows, mosaics, and aquarium-style walls. Placing Blue Stained Glass anywhere above a beacon tints the beacon beam blue, and stacking stained glass of several colors above the same beacon blends the beam into new shades. Hostile mobs treat stained glass as completely opaque, so mobs cannot see players through Blue Stained Glass, and mobs cannot normally spawn on stained glass blocks. Six Blue Stained Glass blocks craft into sixteen blue stained glass panes for thinner window frames. Blue Stained Glass has existed in Minecraft since Java Edition 1.7.2, and Bedrock players have had stained glass since Pocket Edition 1.0.0.