Tiger Coin Charm

Chinese inscription on the reverse is Chen Yin.
The first character Chen means "Dragon sign" - fifth animal sign from the cyclical Chinese calendar.
The second character Yin is a "Tiger sign" - third animal from the Chinese calendar.

The character Chen corresponds to zodiac sign Long - Dragon - and the character Yin corresponds to zodiac sign Hu - Tiger. There are very interesting words combinations of that Chinese characters Long and Hu:

• Long Hu - Dragon and Tiger as a symbol of water and fire; rain and wind; reign and majesty;
  in figurative meaning - elegant handwriting, prominent man.
• Long Hu Dou - "a battle of the Dragon and the Tiger" - a dish from snake's and cat's meat, in the figurative meaning - exotic food.
• Long Hu Bang - a list of persons passed an examination - out of date phrase.
• Long Tiao Hu Wo - jumping Dragon and ambushing Tiger - in the figurative meaning - strong and confident style in calligraphy.
• Long Xiang Hu Bu - a dash of the Dragon and a gait step of the Tiger - in the figurative meaning - courageous, warlike, menacing appearance.
• Long Xiang Hu Shi - a dash of the Dragon and a look of the Tiger - in the figurative meaning - a wide, greedy aspirations, ambitious plans.
• Long Jing Hu Mu - pupils of the Dragon and eyes of the Tiger - in the figurative meaning - fierce look, menacing appearance.
• Long Xing Hu Bu - a flight of the Dragon and a gait step of the Tiger - in the figurative meaning - about majestic appearance.
• Long Yin Hu Xiao - a whistle of the Dragon and a roar of the Tiger - in the figurative meaning - about the loud, ringing voice.
• Long Zheng Hu Dou - a fierce struggle between two evenly-matched opponents [Mr.Y.K.Leung].
• Long Tan Hu Xue - Dragon's pool and Tiger's den - danger ous location [Mr.Y.K.Leung].
• Long Pan Hu Ju - coiling Dragon and crouching Tiger - unpregnable strategic point or strategically located situated place [Mr.Y.K.Leung].
• Long Teng Hu Yo - Dragon's rising and Tiger's leaping - scene of bustling activity [Mr.Y.K.Leung].
• Sheng Long Huo Hu - brimming with energy; full of vigour and vitality [Mr.Y.K.Leung].

In Japanese JNDA catalog (1995) I found (only) obverse image of that charm (p.115, piece N4) with next comments:
Shui Hu Hu Qian - Tong (copper or brass) - Qing Yin 3rd year (a.d.1867)

• Shui - water
• Hu - reigning court
• Hu - Tiger
• Qian - coin (Japanese Sen - 1/100 Yen)
  i.e. name of that coin in that book,is i suppose The Tiger coin of the Water court.