I am just curious about the catalyst that would have led them to making copper tools, if they had to first smelt the ore. I have seen references to Egypt using both stone and copper tools, before going with the more appealing copper.
Thank you.
Smelting was probably an accidental discovery. Two things led to it. First, familiarity with metal, from working with native metals. While most metals are found as ores, rather than in a metallic form, some metals are found as metals. This is most common for gold, which is quite chemically unreactive, but other metals are also found in their metallic form. This includes copper ("native copper"), which was used for ornaments (in the Old World) long before smelting, and for weapons and ornaments (in the Americas, where larger pieces - sometimes big enough to make daggers from - were more common). Iron was also known, mostly in the form of meteoric iron.
Second, pottery. Pottery was an important predecessor of copper smelting, since the temperature achievable in an open fire are insufficient for copper smelting. A pottery kiln, at earthenware temperatures, is hot enough for copper smelting.
Where these come together is colourful glazes for pottery. Copper ores are often very colourful, and would be very natural choices to try for glazing pottery. Given high enough temperatures, and a reducing atmosphere (i.e., oxygen poor, and with carbon monoxide from incomplete burning), copper ore in a glaze will be smelted, and form small drops of copper.
Given prior experience of metals, possibly with native copper, and otherwise possibly with gold, such accidentally-smelted copper can be recognised as metal. Further experimentation can lead to the development of smelting. This appears to have happened at least twice (and possibly no more than twice), once in the Old World, and one in the Americas.
For more detailed past discussion of this, see the answers by me, [deleted], and u/deaconblues99 in:
While you may get good answers on this sub, you could also post this question in r/AskAnthropology, as the period of time you are enquiring about lies before a lot of written history.