Opal Necklace and Dumbledore

[limerent4ever]

No: HPFGUIDX 169691

Hello all!  I am an on and off again lurker for years- mostly off as I
was always overwhelmed by the number of posts here and stupidly never
saw the topic view for some reason till lately. :(

So I was rereading CoS and came to the part where Harry is hiding in
Borgin & Burkes while Draco is browsing the store.  The opal necklace
is stated as 'claiming the lives of nineteen muggle owners to date.' 
So my question is why did Draco seem to think giving it to Dumbledore
would result in his (DD's) death?  I want to say that I am aware that
there might be an easy answer as I haven't reread HBP (or OotP) since
I read it right after it came out. The card also says 'Caution: Do not
touch. Cursed.'  So I take it it must be dangerous to everyone but
especially to muggles.  Is this correct as far as we know?  

Thanks in advance,
limerent