Generated by SassMeister.com.

SassMeister-input.scss

// ----
// libsass (v3.3.2)
// ----

$png: -0px -0px 68px 68px;
$jpg: -0px -68px 260px 260px;
@mixin sprite-width($sprite) {
    width: nth($sprite, 3);
}
@mixin sprite-height($sprite) {
    height: nth($sprite, 4);
}
@function sprite-width($sprite) {
    @return nth($sprite, 3);
}
@function sprite-height($sprite) {
    @return nth($sprite, 4);
}
@mixin sprite-position($sprite) {
    $sprite-offset-x: nth($sprite, 1);
    $sprite-offset-y: nth($sprite, 2);
    background-position: $sprite-offset-x $sprite-offset-y;
}
@mixin sprite($sprite, $display: block) {
    @include sprite-position($sprite);
    background-repeat: no-repeat;
    overflow: hidden;
    display: $display;
    @include sprite-width($sprite);
    @include sprite-height($sprite);
}
.icon {
    background-image: url("../images/sprite.png");
}

// map 
$map: (
  png: $png,
  jpg: $jpg
);

// loop
@each $key, $val in $map {
  .icon-#{$key} {
    @include sprite(map-get($map, $key))
  }
}

SassMeister-output.css

.icon {
  background-image: url("../images/sprite.png");
}

.icon-png {
  background-position: 0px 0px;
  background-repeat: no-repeat;
  overflow: hidden;
  display: block;
  width: 68px;
  height: 68px;
}

.icon-jpg {
  background-position: 0px -68px;
  background-repeat: no-repeat;
  overflow: hidden;
  display: block;
  width: 260px;
  height: 260px;
}