Geminio

Spell Name: Doubling Charm/Curse

Incantation: Geminio

Pronunciation: /dʒɛˈmɪni.oʊ/ je-MIN-ee-oh

Spell Branch: Charms

Magical Discipline(s): Curses; Enchantments

Appearance: Flick wand at target. No visible light.

Description: Creates a duplicate of any object upon which it is cast. As revealed by the goblin Griphook, any copies created are worthless. The duplicate lasts several hours. Magical properties, at least of a Horcrux, are not copied.

The Doubling Charm Geminio is a charm used to duplicate an object, creating an exact replica of that object. It can also be used to curse an object into multiplying repeatedly when touched, where it is called the Gemino Curse.

Taught from the fifth year in charms.

Regulations: None

Skill Level: Intermediate

Etymology: Latin geminare meaning "to double".

References:

• Used by Hermione in Deathly Hallows to copy Salazar Slytherin's locket to hide their tracks from Umbridge.
• A favourite of Lovella Stone[1]
• Gris Hericho duplicates her coffee cup to save washing[2]
• It appeared on a NEWT exam paper in 2009[3]
• Fauna Blake recalls a time memos at the Ministry were cursed with it[4]
• Lucinda Temple suggests it to Eirene Antonopoulos[5]
• Isla Spectre despairs she is not good at it[6]
• Used by Eli Amherst[7]
• Used by Dion Fayette[8]
• Dylan Fleetwood contemplates it[9]
• Amara Báthory uses it[10]
• Margaret Groust uses it[11]
• Casey O'Doherty uses it while presenting as Hexy[12]

Notes:

• HP Wiki[13]

The Doubling Charm was invented by a pair of reclusive twin witches, Helixa and Syna Hyslop, who used it to create duplicates of every item inside their mansion, in which they lived together their whole lives. After their deaths, their relatives finally learned of this practice, discovering two, duplicated sets of hand-written instructions for the spell, one left by each twin.

There was much debate over whether a copy created with the Doubling Charm held the same value as the original, as the two items were impossible to tell apart at first, being identical to one another.[1] However, over time, the copy tended to rot or tarnish more quickly than the original, making it possible to identify eventually. Because of this, the replicas created through this charm are considered to have no value or worth. It is also unknown as to whether or not the Doubling Charm can duplicate living or sentient beings, or if it is able to replicate an object's magical properties. Furthermore, as dictated by the Fundamental Laws of Magic, the Doubling Charm does not affect metaphysical or fundamental entities, such as the soul, as when Hermione Granger used it to create a decoy of Slytherin's Locket, the soul fragment within was not doubled, hence Lord Voldemort's death at the Battle of Hogwarts.

Gemino Curse

An odd characteristic of the spell, for which a solution was never found, was that only the original caster could stop the multiplication of the object. If the caster did not complete their process of casting, the object would continue multiplying indefinitely, stopping only when the copies began to break down. As such, the Doubling Charm can be used to create a single copy, or multiple, depending on the caster's desires. This indefinite replication property can be done deliberately as a security measure, where it is known as the Gemino Curse. This causes objects to begin multiplying out of control when touched by an intruder or potential thief, quickly filling up the space with worthless copies of the original object, and trapping or crushing the trespassers.