Graveyard dirt has many uses, such as cursing/crossing, luck and good fortune, protection, and love
In general:
Communication/summonings of spirits of the dead
Protection from spirit attacks
Banishing someone or something
Dispelling certain emotions
Letting go or breaking habits spells
From specific graves:
Communicating with the spirit who resides there/spirits relating to them
Love and home happiness spells, if gathered from the grave of a loved one
Bravery, strength, or demanding that someone obey you, if gathered from the grave of a soldier
Knowledge, if gathered from the grave of the elderly or one who values gaining knowledge
Healing, if gathered from the gave of an ancestor or healer
Spiritual guidance and protection, if gathered from the grave of a spiritual leader
Innocence, playfulness, and developing new friendships, if gathered from the grave of a child. (Be wary of these; many died unexpectedly and early, so they may be more bewildered than anything.
Strength and protection from harm, if gathered from a grave of one who was abused
Ancestor connection and veneration, if gathered from the grave of a family member
