Prices were very high on day one due to an extremely limited supply and a lot of (warranted) attention. They've since normalized.
Mining is generating Zcash way too fast for the market to absorb. The "market cap" has been holding steady as the priced dropped over 99%.
Somewhere between $2-$10 is a more realistic valuation (based on other coin valuations) -- it will be interesting to see if the price stabilises once within this range.