And if you didn't catch her nails on the show, which aired on Saturday, panic not – good old Nicole handily posted this close-up picture on Instagram yesterday (9 December).
"My saturday #Xfactor nails @elize_nails. In Honour of Nelson Mandela #MADIBA #46664," Nicole wrote.
Nelson Mandela, who was the first black president of South Africa in 1994, passed away at home last week at the age of 95.
And Nicole has been very open about her sadness regarding the news. Speaking on Twitter last week she wrote: "God Bless @NelsonMandela Tears stream as it was an honour to have known u. U were truly exceptional & an inspiration."
The X Factor judge and former Pussycat Doll also paid homage to her icon at the Cosmopolitan Ultimate Women Of The Year Awards last week and has even been rumoured to be performing at Mandela's funeral after reportedly having meetings with his daughters at a hotel in London.
Nicole's latest tribute to her icon was created by celebrity nail technician, Eliza Star who regularly works on The X Factor's stars and contestants.
Here, she painted Nicole's nails to look like the flag of South Africa, before writing 'Madiba' on one hand and the numbers '46664' on the other.
Madiba is Mandela's Xhosa clan name, whereas 46664 refers to Mandela's prisoner number from when he was jailed for over 25 years for high treason.
What do you think of Nicole's tribute to Nelson Mandela? Let us know below. Our fave comment across the site each week wins £50!
Got an iPad or iPhone? Reveal Mag is specially designed to fit!