An 1864 Indian Head Cent with a full LIBERTY and visible diamonds on the headband is a desirable coin for collectors, particularly compared to more worn examples. Here's what affects its value:

Grade:

• While you mentioned "full Liberty and diamonds," an official grade from a professional grading service (PCGS or NGC) is crucial for determining the coin's exact value. Grading considers various factors like:
  • Luster: Mint shine remaining on the surface.
  • Strike: Sharpness of details from the die transfer.
  • Surface preservation: Absence of scratches, nicks, or other wear.
• Here's a general value range based on possible grades:
  • Good (G): $15 - $20 (Liberty might be faint, few to no diamonds visible)
  • Very Fine (VF): $58 - $80 (Full Liberty, some diamond details)
  • Extra Fine (XF): $100 - $200+ (Most or all diamonds visible)
  • Almost Uncirculated (AU): $300 - $1000+ (Very sharp details, most or all mint luster remaining)

Diamonds:

• The number of visible diamonds on the headband can influence value within a grade. More visible diamonds generally indicate less wear and a higher potential value.

Full Liberty:

• A fully readable "LIBERTY" inscription is important. Worn letters can decrease value.

Other Factors:

• Mintmark: There's no mintmark on most 1864 Indian Head cents (produced in Philadelphia). However, a rare variety exists with an "L" mintmark denoting coinage in New Orleans. This is a valuable collector's item.
• Toning: Natural toning can add aesthetic appeal and value, but excessively dark or unattractive toning can detract.

Recommendations:

• For an accurate value, get your coin graded by a professional service like PCGS or NGC.
• Research online auction results and dealer listings of similarly graded 1864 Indian Head cents with full Liberty and visible diamonds to understand current market prices.