1 teaspoon of cream of tartar is a small amount of powder that weighs 0.139 oz (3.94 g). When poured into a loose pile, it is 1.37 in (3.47 cm) wide and 0.615 in (1.56 cm) tall, which is about half the size of a cherry.

In kitchen measures
1 teaspoons
1 tsp · 0.333 tbsp · 0.021 cups
about half the size of a cherry
Cream of tartar typically ranges 0.75–0.85 g/mL depending on how it's packed. A firmly packed scoop weighs more.