I noticed tonight that Heavenly Shard is used for the new Tome of Illusions: Cataclysm and therefor i checked the price on Maelstrom Crystal  which goes for around 30g each on my server. You can use disenchanting to shatter it into 2 Heavenly Shard  which sells for around 35 g each on my server.
That is twice as much that you actually pay.

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