Your answer is radiometric dating
Answer:
A. Obsidian
Explanation:
It fits the property described in the question.
It cools so fast that no visible crystal or grain could form. It has high silica Composition, black and glassy. It is also used to make tools with sharp edges
Hi, let us know what your list of countries is!
In the meantime, I will give you some information, hopefully it will help:
In constitutional monarchies the Head of state, the monarch is only ceremonial. this includes for example all the European monarchies, all the countries in which the British Monarch is the head of state and Japan.
Also, in parliamentary systems the head of state, the president is also ceremonial. This includes The central European democracies (Germany, Austria) and India and Pakistan)