You can achieve this like this.
Code:
sub EVENT_CONNECT {
quest::settimer("Crystals", 3600);
}
sub EVENT_TIMER {
if ($timer eq "Crystals") {
quest::stoptimer("Crystals");
my $radiant = quest::ChooseRandom(1..5);
my $ebon = quest::ChooseRandom(1..5);
$client->AddCrystals($radiant, $ebon);
$client->Message(315, "You have recieved $radiant Radiant Crystals and $ebon Ebon Crystals. You now have " . plugin::commify($client->GetRadiantCrystals()) . " Radiant Crystals and " . plugin::commify($client->GetEbonCrystals()) . " Ebon Crystals.");
quest::settimer("Crystals", 3600);
}
}