Elvengrass is a special, magical block that doesn't naturally spawn anywhere. It is formed by right-clicking on a grass block (based on vanilla dirt) with Edhelvir, consuming the crystal in the process. For this to work you either need 1 High elven or 1 Lothlórien alignment.
Note that this does not hold for jungle grass, that is based on jungle mud.
An Elvengrass block resembles an ordinary grass block, but is blue-tinted instead of green and emits blue smoke. When destroyed it will only drop dirt unless a tool modified with Silken is used.
Uses[]
This block is used for the frame when making Elven portals to the overworld. A minimum of 12 blocks are needed for this purpose, arranged in a 5x5 frame with the corners cut off.
The blocks also serve as the base on which large mallorn trees can be grown. 25 blocks are needed for this purpose, arranged in a 5x5 square.
Trivia[]
As jungle grass doesn't spread to vanilla dirt, creation of an elven portal in the Far Harad Jungle requires the local creation of vanilla grass blocks.
As of Public Beta 28 this can be done by right clicking the locally available vanilla dirt (mine for that stuff!), with grass seeds.
  The High Elves of the West  
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 The Wood-elves of Lothlórien 
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Elf (Banner Bearer, Warden, Warrior)
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