It's no longer legal tender and ceased to be so after the 31st of August of 1971.
The Phonetic Dictionary of the English Language of 1913 by Hermann Michaelis and Daniel Jones offers these transcriptions of threepence:
The three vowels /ɪ, e, ʌ/ are the most frequent ones together with the FOOT vowel, which can be found in the EPD from its 4th ed. of 1937 onward. Only rarely, however, do we come across a schwa in the first syllable, e.g.
- in the Concise Pronouncing Dictionary of British and American English of 1972 by JWL
- in the Advanced Learner's Dictionary of Current English of 1974 (3rd ed. only!) by A.S. Hornby et al.:
- in the Longman Dictionary of the English Language of 1984:
(u stands for the vowel in luck and i for lick)
- in the Cambridge Advanced Learner's Dictionary of 2008 (3rd ed.):
Do you like ðə θrəpn̩i ˈɒprə?
There are more beautiful terms for coins such as florin, farthing, sovereign, guinea, crown, groat.