And that matrix has to be removed little by little, bit by bit.

须是一点儿一点儿被移开的。

They're encased in their host rock, which is what we call matrix.

它被包裹在寄主石中，我为。

When the molten rock solidifies, its mineral makeup is not the same as that of the original parent.

当熔凝固时，其矿物组成与原始不同。