1. Geologists use physical properties to identify minerals. For example, the blank cleavage, color, fracture, hardness, luster, specific, gravity, streak, texture

The correct answer is - crystal form (external shape).

Explanation:

Physical properties are used for the identification of the minerals that include specific gravity, streak, texture, luster color, hardness, cleavage, and crystal form.

The most common physical property of the minerals in crystal form or external shape of the mineral. This is the property of the mineral that gives an idea about the homogenous possessing a 3-D internal order.

amber has allowed scientists to study dna that has been preserved over millions of years.