Introduction:
Ionic bonding is a type of chemical bonding that occurs when there is a transfer of electrons between atoms. This results in the formation of charged particles called ions, which are held together by electrostatic forces of attraction. In an ionic bond, one atom loses electrons while another atom gains those electrons.

Explanation:
The given question asks which of the following is not a property of an ionic bond. Let's analyze each option to determine the correct answer.

a) Losing of electrons:
In an ionic bond, one atom loses electrons. This is a characteristic property of an ionic bond. When an atom loses one or more electrons, it becomes positively charged and is called a cation.

b) Gain of electrons:
In an ionic bond, another atom gains the electrons that are lost by the first atom. This is also a characteristic property of an ionic bond. When an atom gains one or more electrons, it becomes negatively charged and is called an anion.

c) Sharing of electrons:
Sharing of electrons is not a property of an ionic bond. Instead, it is a property of a covalent bond. In a covalent bond, atoms share electrons to achieve a stable electron configuration. This sharing of electrons allows atoms to fill their valence shells and form molecules.

d) Transfer of electrons:
The transfer of electrons is a fundamental property of an ionic bond. In an ionic bond, electrons are transferred from one atom to another, resulting in the formation of cations and anions. This transfer of electrons creates a strong electrostatic attraction between the oppositely charged ions, leading to the formation of an ionic compound.

Conclusion:
Based on the analysis, the correct answer is option 'c', which states that sharing of electrons is not a property of an ionic bond. Ionic bonding involves the transfer of electrons, leading to the formation of ions.