Bought several golden pearls on a show - wonder if they are real

[nickie]

Recently on an Intergem show I bought several golden pearls from a vendor unknown to me. There was no opportunity to make holes during the show, but I had a holing machine at home and expected no problems, having successfully drilled pearls before.
The pearls were unusually hard, regular 0.8 mm drill did not take them, so we changed it to a larger one, and it took me and my friend a long time to drill huge holes in a couple of pearls. The smell was strange, of burned wool.
I bought several longer drills from different sources. To no avail, 0.8 mm could not even penetrate the core.
At the same time, I easily drill Tahitians of all sizes with the drills from the same package, so it is not about the drills.
My question is, are there natural golden pearls with harder core, and is there any better kind of drills?
Or was I unlucky enough to buy something manmade? Or is there a trick to be used with golden pearls?

 

[LondonPearl]

Post some images!!!

 

[pearlescence]

Drilling depends on what nucleus the pearl farmer has used. I have had lots of all types of pearls where some are easy to drill and some have nuclei so hard I have seen the drill bit bend and dig a groove in the nacre rather than penetrate the nucleus. Other times I've had to change bit half way through because the bit went blunt.
Drilling can always surprise you

 

[ericw]

It's indeed a matter to ask farmers what they put in their pearls. I have seen several drills breaking or heating abnormaly if nucleus was made with nacre. I even received half drilled pearls where worker had broken a first drill, and made a second hole near the first.. enjoy!

 

[pearlescence]

Pearls with two drill holes like that should not be sold, unless it is clearly stated and very cheaply. When that happens with good pearls (and it does) those are the pearls we keep for ourselves.

 

[nickie]

Thank you all for your answers! The pearls are so pretty and the vendor was nice too...I would really feel bad if they were synthetic. I shall post photos and also take the rest to my jeweler and see what he says. (He has no problems drilling holes in golden pearls from other vendors). That the drills do not come sturdy in general I have noticed. Maybe making a tiny hole first and then drilling through it would be a good idea.

 

[nickie]

Interestingly, today I walked into an unknown store selling cheap manmade as well as expensive pearls and asked the same question.

They said that normal cultured pearls are usually OK to drill. This is varnish coating on imitation golden that is a problem for drilling, they said.

So i really want to send this pearl for proper certification. I kept the receipt - if these pearls are not what he claimed they are, the vendor should reimburse me. I shall take the photo, too.

 

[pearlescence]

If you reflect..the stress on a sliver of metal rotating at high speed and being pushed into a hard object is huge. Small bits go blunt after a few pearls and need to be sharpened (which I have never managed to get the knack of) or discarded and replaced.
I reckon yours are real pearls if the nacre fits all the real nacre tests. sometimes farmers use hard nuclei. I think they don't do it again when the pearl factories complain as they do most of the pearl drilling
The stuff about varnish coating on imitation golden sounds like rubbish.