<?php
   $allImmunities = array(
    'poisonPercent' => '/images/gems/earth.gif',
    'earthPercent' => '/images/gems/earth.gif',
    'paralyzePercent' => '/images/gems/paralyze.gif',
    'deathPercent' => '/images/gems/death.gif',
    'energyPercent' => '/images/gems/energy.gif',
    'icePercent' => '/images/gems/ice.gif',
    'firePercent' => '/images/gems/fire.gif',
    'physicalPercent' => '/images/gems/physical.gif',
    'holyPercent' => '/images/gems/holly.gif',
    'invisiblePercent' => '/images/gems/invisible.gif'
   );

$data = 'physicalPercent:10, icePercent:10, holyPercent:-10';
foreach(explode(', ', $data) as $prop) {
   list($propName, $propVal) = explode(':', $prop);
   // $propName would be physicalPercent,
   // $propVal would be 10 for the first iteration, etc

   // now get the image
   $img = $allImmunities[$propName];

   echo $img ."\n";
}