Here's why:

* Interlocking crystals: This indicates that the rock has undergone metamorphosis, where heat and pressure have caused existing minerals to recrystallize.

* Not lined up: This means the crystals don't exhibit a preferred orientation.

Examples of non-foliated metamorphic rocks include:

* Marble: Formed from limestone, with interlocking calcite crystals.

* Quartzite: Formed from sandstone, with interlocking quartz crystals.

* Hornfels: Formed when other rocks are baked by nearby intrusions of magma.

Let me know if you want more information about any of these rocks!