Minecraft wiki entry for Block_of_Quartz, associated text: The first screenshot released about the quartz block.
An example of how quartz blocks can be used to simulate marble or limestone.
An example showing how pillar quartz blocks can be placed.
The second Redstone Update Pre-release Banner.
Formerly all blocks that can be rotated in Bedrock Edition, including both variants of quartz
Comparison of regular and smooth quartz underside textures in prior versions of Java and Bedrock edition.
An early Pocket Edition comparison of a double quartz slab and a block of quartz, mirroring the 1.14 situation.