This five-sided dice is based on a pentagonal trapezohedron modified such that it will only land on 1 of 5 sides with equal frequency, resulting in a fair shard-shaped d5.
New three-sided, four-sided, six-sided, and eight-sided versions are available
here.
See also:
d3 shard
d5 shard
d5 vowel shard
d7 shard
polyhedral rpg shard set
d21 shard
d21 consonant shard