I have a few modern Ethiopian coins, so I thought I'd try learning how to read off the dates. Here's one of the references I used. As far as I understand, there is no number for zero used. There is a separate number for each multiple of ten, which doesn't necessarily resemble the corresponding 1s digit. So 20 = ፳, its own single symbol, which is not similar to 2 = ፪ etc. Numbers helpfully have brackets above and below them, which make them easier to distinguish from words. Thousands and hundreds are represented by a tens multiple plus a units digit, followed by the character for 100: ፻. So for the top two coins, the dates are both ፲፱፻፴፮, which is the characters for: 10, 9, 100, 30 and 6. That indicates 19 100s + 30 + 6 = 1936. The Ethiopian calendar is a Christian calendar, but it differs from the Gregorian calendar by being 7 or 8 years later in its starting date, which is based on the Annunciation. So 1936 in the Ethiopian calendar is 1944 AD. The Ethiopian calendar starts around September, and is a solar calendar. Because the New Year dates don't line up, the difference is 7 years behind from Sep - Dec, and 8 years from Jan - Sep or so. But for most coins you can just add 8 to the Ethiopian year to get the AD year. The third coin is dated ፲፱፻፷፱, which is = (10 + 9)*100 + 60 + 9 = 1969 = 1977 AD. The coins are clockwise from top L: 5 Santeem, 1944; 10 Santeem 1944; 50 Santeem 1977. I'm still a complete beginner, so please feel free to point out any errors or helpful resources, or to post any other Ethiopian coins!
I cheat and use the Wildman coin catalog software that has date converters. I'll have to see what it says for Ethiopia.
Here are a couple of Ethiopian notes that I picked up while in Addis Ababa several years ago. It was surprisingly hard to get coins when I was there.
151 Ethopian Birr is equal to $4.28 today. I gave the lady a $20 (had to be crisp because she refused anything with folds or wrinkles) and I got a stack of Birr back
Spurred on by my previous attempts, I checked my local coin shop and nearly cleared out their entire Ethiopian coin section. Not very hard--it was only a handful of coins and cost less than US $20. First two coins: 1 Ghersh, Menelik II, ፲፰፺፩ 1895 = 1903 AD (silver) 25 Matonas, Hailé Selassié I, ፲፱፳፫ 1923 = 1931 AD (Nickel) Next 3: 1, 5 and 10 Santeem, Hailé Selassié I, ፲፱፻፴፮ 1936 = 1944 AD Next 4: Modern (post-Imperial) 5 Santeem, Brass, Derg Socialist Junta, ፲፱፻፷፱ 1969 = 1977 AD 10 Santeem, Brass, Derg Socialist Junta, ፲፱፻፷፱ 1969 = 1977 AD 25 Santeem, Nickle-plated Steel, Federal Democratic Republic of Ethiopia ፪ሺህ 2000 = 2008 ሺ is the word "thousand" (ši) rather than the numeral, which is ፼. Thus the lack of brackets over and below it. I don't know what ህ means, but I assume the word "year" or something similar. 50 Santeem, Cu-Ni, Derg Socialist Junta, ፲፱፻፷፱ 1969 = 1977 AD Interestingly, the coin designs were almost unchanged after the end of the socialist government. Perhaps because they chose a national symbol (the lion) rather than explicitly socialist imagery. The imperial-era coins all have the Lion of Judah: a lion carrying a crossed scepter at an angle representing the Imperial family and its purported Solomonic lineage.
I just found out that Amharic numerals are just based on Greek numerals via Coptic. They are not even that hard to make out once you know what they match up to. So the reason that 1 looks nothing like 10 is that 1 resembles a lower case a/alpha, while 10 looks like an I/iota. Unlike Greek, they don't have a third set of letters for numbers past 100. So 1000s are just 10s of 100s, using the letter P/rho to indicate hundreds. This totally blows my mind. I can almost sightread numbers without a reference now that I know what they correlate with! 1 2 3 4 5 6 7 8 9 10 20 30 40 50 60 70 80 90 100 (source) Ethiopic ፩ ፪ ፫ ፬ ፭ ፮ ፯ ፰ ፱ ፲ ፳ ፴ ፵ ፶ ፷ ፸ ፹ ፺ ፻ Greek Α Β Γ Δ Ε Ϛ Ζ Η Θ Ι Κ Λ Μ Ν Ξ Ο Π Ϙ Ρ Coptic Ⲁ Ⲃ Ⲅ Ⲇ Ⲉ Ⲋ Ⲍ Ⲏ Ⲑ Ⲓ Ⲕ Ⲗ Ⲙ Ⲛ Ⲝ Ⲟ Ⲡ Ϥ Ⲣ Example: Date is equivalent to iota-theta-rho-xi-theta = (10 + 9)*100 + 60 + 9 = 1969 (plus 8 to get 1977 AD)
Stigma. It's obsolete. I didn't even notice it was different from lower case sigma until you pointed it out.
Update: I posted a summary of my notes with a few additions to my personal coin blog. Only a few additional details if you've already seen this thread. As for the weird Greek letters, apparently Greek numerals use 3 obsolete letters to have enough to represent a 3 digit number: stigma (Ϛ), koppa (Ϙ) and sampi () for 6, 90 and 900. Amharic only uses numbers up to 100, unlike Greek, so there are no numerals for 200-900. But it does use the analogues of stigma and koppa for 6 and 90.