Coinbase halts ether and litecoin trading as cryptocurrency market approaches $500 billion

Coinbase, the popular cryptocurrency trading platform, blocked users Tuesday from buying red-hot litecoin and ether. 
Investors poured into the two red-hot digital currencies Tuesday morning, pushing them both to new heights.Litecoin hit a record of $312 on Tuesday, while ether soared over to more than $600 for the first time.
The cryptocurrency market is gunning for $500 billion. 
 
Cryptomania has propelled two lesser-known cryptocurrencies to record highs Tuesday, forcing one