Opal Block

https://growtopiawiki.nbg1.your-objectstorage.com/uploads/8/8f/ItemSprites.png Crystal Harmonization
Combine the following crystals together:
https://growtopiawiki.nbg1.your-objectstorage.com/uploads/8/8f/ItemSprites.png + https://growtopiawiki.nbg1.your-objectstorage.com/uploads/8/8f/ItemSprites.png + https://growtopiawiki.nbg1.your-objectstorage.com/uploads/8/8f/ItemSprites.png + https://growtopiawiki.nbg1.your-objectstorage.com/uploads/8/8f/ItemSprites.png + https://growtopiawiki.nbg1.your-objectstorage.com/uploads/8/8f/ItemSprites.png
Harmonize and break the resultant crystal to obtain items.

Opal Block is a block introduced during the Strange Crystals update.