Pour elderberry and lemon juice in large kettle. Add sugar and stir to mix. Place over high heat and bring to a boil, stirring constantly. Stir in pectin, bring to full rolling boil and boil hard 1 minute, stirring constantly. Remove from heat and skim off foam. Ladle into sterilized hot jelly jars allowing 1/4" head space. Follow manufacturer's instructions for preparing 2 piece lid. Process in a boiling water bath for 10 minutes. Start timing when water returns to a boil.