Blackboards are blocks added in the 2.1.7 update. They are used as an alternative to Showcases for creating Pixel Art. Up to four dye-able blocks called Pixel Blocks can be placed in an individual blackboard. The advantage of this new block is that players are able to display text or images on a visible scale, instead of having to build much larger structures and wasting much more valuable materials.
A Blackboard is crafted using four compact stone in a Mason Bench in the fashion shown below.
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