There is a man in Varrock who needs a bit of help. He is of noble heritage, but without his family's crest, he can't prove it. Unfortunately, his three sons took the crest with them when they left, scattering all across RuneScape.
Head to Catherby and talk to Caleb in one of the buildings north of the bank, give him Shrimp, Salmon, Tuna, Bass and Swordfish to receive the first crest piece. Speak to him AGAIN after giving him them. Ask him where the rest of the crest is to proceed.
Go north of the Gem Trader to the scorpion mining pit, and speak to the 'Man' with the yellow cape there (Avan).
Teleport to Falador, head down the Dwarven Mines entrance at the east of the city. Once inside head a little north and then west to where the anvils and dwarven NPC's are, and speak to a character named Boot, who is found a bit west from the anvils.
Teleport to Ardougne, head east and go down the dungeon near Witchaven and Ardougne ship port. (Dungeon symbol on world map).
Run through the dungeon (not through the wall). There is a north room, a south room, and a room in the middle east where hellhounds and the perfect gold ore is.
Go to the north wall and pull the lever (up), then the south room and pull that lever (up), back to the north wall and pull the lever (down), then go in the north room and pull that lever (up), go outside and pull the lever on the north wall (up), then pull the lever in the south room (down).
Go into the hellhound room and mine 2 perfect gold ores.
Go to a furnace (Falador/Al Kharid) smelt the ores into bars, then use the bars on the furnace again and make one Ruby Necklace and one Ruby Ring with the rubies and moulds in your inventory.
Go back to the 'Man' (Avan) and give him the jewellery to receive the second crest piece.
Teleport to Varrock, and head north east to the Jolly Boar Inn near the lumber yard. Once there, go upstairs and speak to Johnathon. After speaking to him, right-click and use your anti-poison potion on him and he will tell you where the last piece is.
Go to Edgeville (Amulet of Glory teleport), and get ready for a fight, bring runes for each of the four blast spells as you need to HIT with each spell at least once. Maging is recommended as Chronozon is quite easy to kill and you can safespot without taking any damage. There are poison spiders in the dungeon which can poison you so anti-poison is recommended. Chronozon's area is part of the Wilderness and other players can attack you there.
Go south of Edgeville bank and head down to ladder to the dungeon, navigate through the dungeon and go through the gate where Chaos druids are, go west past them through another gate and the Chronozon is south of the black demons. He is pretty easy to safespot behind the rocks, cast each blast spell on the Chronozon and make sure they all hit damage, then finish him off how you like and take the last crest piece.
Use the crest pieces together to form the Family crest and head back to Dimintheis in Varrock to finish the quest.