En el RIC la rareza es según el volumen
Roman Imperial Coins (RIC)
Rarity Ratings
RIC I (1984)
C: Common to very common
S: Scarce
R: Rare
R2: [Rare] 11-15 known [in the collections examined]
R3: [Rare] 6 to 10 known [in the collections examined]
R4: [Rare] 2 to 5 known [in the collections examined]
R5: [Rare] Unique [in the collections examined]
RIC II (late 1920's)
Unspecified, probably the same as RIC I
RIC II,
Part I, Second Fully Revised Edition (2007)
C2: Extremely common
C: Common
R: Rare
R2: Very rare
R3 - Unique [only one in the collections examined]
RIC III (1930)
Unspecified, probably the same as RIC I
RIC IV (1934)
Unspecified, probably the same as RIC I
RIC V(1927/1933)
CC: Very common
C: Common
S: Scarce
R: Rare
R2-R4: [Rare] Additional degrees of rarity
R5: Unique [only one in the collections examined]
RIC VI (1967)
C2: [Very] Common in every major collection
C: [Common] In every major collection
S: [Scarce] In most major collections
R: [Rare] 26-50 coins known [in the collections examined]
R2: [Rare] 11-25 coins known [in the collections examined]
R3: [Rare] 6-10 coins known [in the collections examined]
R4: [Very Rare] 2-5 coins known [in the collections examined]
R5: Unique [only one in the collections examined]
RIC VII (1966)
C3: [Common] more than 41 coins known
C2: [Common] 31-40 coins known
C1: [Common] 22-30 coins known
S: [Scarce] 16-21 coins known
R1: [Rare] 11-15 coins known
R2: [Rare] 7-10 coins known
R3: [Rare] 4-6 coins known
R4: [Very Rare] 2-3 coins known
R5: Unique [only one in the collections examined]
RIC VIII (1981)
Unspecified, probably similar to RIC VI or VII
RIC IX (1933)
C-C3: [Common with] increasing degrees of commonness
S: Scarce
R-R4: [Rare with] increasing degrees of rarity
R5: Unique [only one in the collections examined]
RIC X (1994)
Unspecified, probably similar to RIC VI or VII
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