We have already discussed quite a few transfiguration spells as duelling spells in this book.

Another important transfiguration spell that may be useful in duelling in situations when glass projectiles or broken glass shards from the Reductor curse are flying towards you or similar situations is the Glass to Sand Shield Charm. It was used by our Professor Jericho Penrose during Auror training.

Effect: - Transforms glass to sand.

Spell Type: - Defensive.

Spell Block: - 

Incantation- Contrita Specularma, pronounced as CON-tree-ta-spek-u-LARH-mah.

Wand Movement- Point wand at glass.

Willpower- Low.

Concentration- Low, Visualize the glass breaking and disintegrating, especially focusing on the small pieces of sand.

One important thing to note is that for all transfiguration spells, visualization of the transfiguration happening, and visualization of the exact final transfigured object along with it's intricate details is necessary.