NGK makes two types of iridium tipped plugs. Most if not all iridium tipped plugs that are OEM for the manufacturers have an iridium center electrode and a platinum disk on the ground electrode. These are good for about 120k.
They also make some with just an iron ground. They make these for cars that did not come with iridium plugs from the factory. These do not last as long as the iron erodes. They should be changed every 30-40k miles.
The plugs look fine to me. Now if there was some wet liquid oil on the end of the threads then it would be time to worry because that means a piston ring issue in most cases.
I’m in the camp that says the plugs look fine. Perfectly normal. I think circuitsmth explained why perfectly.
As regards the gap, a set of feeler gages is dirt cheap and well worth the cost of checking them makes you feel better. Be sure to check the recommended gap and not make any assumptions. Iridium plugs do use different gaps. The discharge end (the iridium electrode, the one from which the discharge comes) concentrates the spark better, and that allows a different gap. There’s a perception that iridium tips look eroded, but in reality they don’t… they just look different due to their small diameter. Eroded electrodes look rounded on the ends with less material protruding above the ceramic insulator.
I commend you for taking care of your engine. I hope you changed the spark plugs rather than reusing them. These plugs have a flat shoulder with a hollow metal “crush washer” on it that crushes to conform to the irregularities of the surfaces creating a positive seal, and once used they preferably should not be reused. Once crushed, the washers won’t spring back and crush again when reinstalled. The positive seal is compromised.
Thank you so much for the reply, very informative. I changed them, immediately, runs fine. Heard several opinions. Will inform dealer and monitor.