Glass

Glass is a decorative and fully transparent solid block that can be dyed into stained glass, or crafted into tinted glass.

Breaking
Glass drops itself only if it is broken with a tool enchanted with Silk Touch; otherwise, it drops nothing.

Natural generation
A secret room containing glass can be found inside woodland mansions. Glass is also generated in ancient cities.
 * Glass

Magenta stained glass blocks naturally generate as windows in end cities.
 * Stained glass

Trading
Journeyman-level librarian villagers have a 50% chance to sell 4 glass for 1 emerald.

Journeyman-level librarian villagers have a $2/3$ chance to sell 4 glass for 1 emerald.

Usage
Glass blocks adjacent to other glass blocks are invisible when viewed through glass.

Mobs cannot normally spawn on glass blocks. An exception to this is zombie reinforcement, which can result in unexpected zombies "sneaking into" an otherwise secure area. Glass blocks (but not glass panes) also block a mob's line of sight for the purposes of aggro; e.g. a zombie will not begin targeting a player if there are glass blocks between the player's eye level and the zombie's eye level, though it can still pathfind around them. Mobs may also still look at the player through the glass, but this is purely visual.

Redstone dust and components can be placed on glass, but cannot power glass. Glass can't cut vertical redstone. Vertical redstone can be placed on glass. $$, it transmits redstone signals up, not down. Otherwise, glass in redstone circuits is functionally the same as an upside-down slab.

Light does not travel through tinted glass blocks.

ID




Trivia

 * Before stained glass was added, there was a similar block named tinted glass in the April Fools version 2.0, which had the same use. The texture for the April Fools block was used for one snapshot before it was replaced.