You will need...
Gold picture hanging wire (about £1.50 from Wilkinson)
About 5 black drinking straws (free at all participating restaurants)
The string of an old necklace or pendant
Long nosed pliers
For the method I used...
Fimo gold powder (about £3 if you shop around)
A little fiddly in places and picture hanging wire splits really easily, which can be a headache when you're trying to join pieces together.
I'm going to say an hour each but, thanks to nearby distractions, I think I made heavier weather of it than I needed to. Also, I'd recommend a quicker, simpler method than the one I did (and learnt from) as I'll explain later on.
Wire it up...
I constructed each pyramid by making 3 flat wire triangles, joining the ends together by bending them back on themselves, hooking them together and locking them in place with a twist of the pliers; I inserted them into pieces of straw as I went along (not pictured). Each side was 3cm long.
After I made each pyramid, I threaded the cord through the jump rings at the top and alternated them with a 3cm straw "stoppers" so that they stayed spread out.