♆

• – the symbol commonly has barbs on the tines.
• – orbed variant common in German-language sources alongside ⟨♁⟩ for the Earth and ⟨⛢⟩ for Uranus, so that most of the planetary symbols contain an orb; sometimes with horizontal barbs on the outer tines so that those look like an inverted omega, ⟨℧⟩.
• – another common variant today; this form of Neptune's trident was used by Newton as a symbol for bismuth, before the planet Neptune had been discovered. Typefaces that use this form may harmonize it with Jupiter so that it looks like ⟨⟩ reflected on itself.[1]
• Ψ – Greek capital letter psi is sometimes used as a typographic substitute.

When the symbol has a cross at bottom and the tines do not bear barbs, it may be identical to variants of ⟨🝁⟩, an alchemical symbol for for quicklime.

The trident of Neptune, the Ancient Roman god of the sea.[2]

♆

1. (astronomy, astrology) Neptune.
2. (alchemy, archaic) bismuth.
3. (military) a common component of naval emblems.

As one of several alchemical symbols for bismuth, Neptune's trident is not attested with barbs on the tines, and is unlikely to have ever had a planetary cross or orb at bottom, but a distinct character is not available in Unicode, and it is identical to the design of the planetary symbol in some typefaces.

• (astronomy): ⯉
• Ψ

• (alchemy): 🜾 – bismuth ore

• 
  A barbed variant
• 
  German orbed variant
• 
  Variant used by Newton for bismuth
• 
  A decorative crossed variant in the Netherlands
• 
  A decorative orbed variant in the Netherlands
• 
  An abstract variant
• 
  Symbol on a sea-green background
• 
  Transit of Neptune
• 
  A graphic substitute, Ψ
• 
  Neptune's trident in the emblem of a naval outfit