Crystal ball

Used since Antiquity, crystal balls have had a broad reputation with witchcraft, including modern times with charlatan acts and amusements at circus venues, festivals, etc.

Other names for the thing include crystal sphere, orbuculum, scrying ball, shew/show(ing) stone, pondering orb, and more variants by dialect.

[10] Crystal ball scrying is commonly used to seek supernatural guidance while making difficult decisions in one's life (e.g., matters of love or finances).

For typical materials such as quartz and glass, it forms an image of distant objects slightly beyond the surface of the sphere, on the opposite side.

The image of the sun formed by a large crystal ball will burn a hand that is holding it, and can ignite dark-coloured flammable material placed near it.

[17] Weighing 49 pounds (22 kg), the sphere is made of quartz crystal from Burma and was shaped through years of constant rotation in a semi-cylindrical container filled with emery, garnet powder, and water.

The ornamental treasure was purportedly made for the Empress Dowager Cixi (1835–1908) during the Qing dynasty in the 19th century, but no evidence as to its actual origins exists.