Which ice type is used predominantly for cocktails served on the rocks?

The use of ice cubes in cocktails served on the rocks is primarily due to their ability to chill drinks effectively while maintaining their structure and not overly diluting them. Ice cubes are designed to fit into a glass conveniently and can hold their shape longer than crushed or liquified ice, providing a consistent and pleasant drinking experience. This balance allows for the cocktail to maintain its intended flavor profile without excessive watering down.

In contrast, crushed ice tends to melt more rapidly, which can lead to dilution of the cocktail and alter its flavors. Liquified ice, which is essentially water, would not provide any chilling effect or texture, making it unsuitable for cocktails. Block ice, while it can also be used in some contexts, is generally more suitable for chilling larger quantities or for presentation rather than in individual drinks served on the rocks. Therefore, the choice of ice cubes strikes the right balance between cooling the drink and preserving its integrity.