The question was not popular among  the candidates.  Mine development is the series of activities involved in opening a mineral deposit for production.  The natural factors in mine development are:

• topography
• boundary of the concession
• location of the concessions
• physical features of the concession
• size of the deposit
• shape of the deposit
• height of the deposit (if exposed)
• scattered nature of the deposit

The Geologic considerations are :

• mineral constituents of the host rock
• element constituents of the minerals
• age of formation
• temperature of the rock
• presence of the water/water constituents
• dip of the surrounding rock
• dip of the ore
• strike of the surrounding rock
• strike of the mineral
•  

Other considerations are;

• rock mechanics properties (e.g. hardness of the ore, hardness of the surrounding rock, compressive strength of the ore, tensile strength of the ore)
• chemical and metallurgical properties (e.g. how the mineral reacts with water and other chemicals, how the surrounding rock react with water, chemical reaction of mineral with other chemicals, chemical composition, reaction of mineral with air)

The mineral titles in the Nigeria Minerals and Mining Regulations,  2011 are:

• Reconnaissance Permit
• Exploration License
• Small Scale Mining Lease
• Mining Lease
• Quarry Lease
• Water Use Permit