Multi-dimensional each loop in Scss

each.scss

// Irregular Sprite List
// The following icons have varying dimensions
// Key: icon-name background-position-x, background-position-y, absolute-position-x, absolute-position-y, width, height

$irregular-list:
  dashboard -69px 0 45px 29px 46px 45px,
  download -23px -121px 0 6px 33px 26px,
  head-double -69px -123px 40px 34px 58px 36px,
  head-stats -69px -46px 44px 31px 55px 39px,
  head-with-tie -69px -85px 45px 34px 44px 37px,
  image 0 -120px 0 0 20px 27px,
  newsletter -23px -100px 0 0 45px 20px;

@each $icon in $irregular-list {
  .icon-#{nth($icon, 1)} {
    position: relative;

    &:before {
      background: image-url('icons/icons-sprite.png') no-repeat;
      background-position: #{nth($icon, 2)} #{nth($icon, 3)};
      content: '';
      left: #{nth($icon, 4)};
      height: #{nth($icon, 7)};
      position: absolute;
      top: #{nth($icon, 5)};
      width: #{nth($icon, 6)};
    }
  }
}