If ice is warmed and becomes a liquid, the process is endothermic.
The process requires heat in order to proceed. If ice stays in a very cold place, it will not melt unless it's heated. If ice is placed outside where it melts on its own, it gets the heat from the surroundings.
A. Fireworks exploding is the answer
There are multiple factors that contribute to the cost of a mineral.
First of all is the demand or application, which will be related to its
physical properties. For example, nontarnishing metals like gold are
held in high value for their appearance. Second is the supply of the
mineral, those that only have a small quantity in the earth's crust are
likely to be more expensive. Third is the cost of extraction and
manufacturing. Some minerals may be abundantly found, but may be
distributed over a wide area, meaning that it is still expensive to mine
and transport.