* Age: Decanters from older years or limited editions may have higher values.
* Condition: Decanters in good condition, without chips, cracks, or significant wear, will generally be more valuable.
* Rarity: Some decanters may be more limited or rare, which can increase their value.
It's always a good idea to consult with an expert or check reputable sources to get an accurate valuation for a specific decanter.