It's official! Kat Von D proudly shows off her black diamond engagement ring as she holds hands with fiance Deadmau5

They've been on and off like a leaky faucet but after spending Christmas with Deadmau5's family; Kat Von D is sporting a piece of jewellery that screams commitment. 

The doyenne of the tattoo parlour showed off a black diamond engagement ring; an expensive promise she obviously received over Christmas at music producer and DJ's family home. 

Fans of Deadmau5 know the ring has been a work in progress. 

Unique: Kat Von D flashed her engagement ring as she arrived in Vancouver with her fiance DJ Deadmau5 on Thursday; the ring's been subject to some alterations... not least changing the clear diamond to black

He initially Tweeted a picture of what could've been a stock ring. 

It comprised a huge diamond flanked by silver or platinum skulls but he noted that the ring was to be changed to a black stone for his gothic lover. 

And the sparkler Kat was showing off was certainly obsidian; and very in keeping with the raven-haired beauty's look. 

Black diamond: Deadmau5 Tweeted a picture of the ring in progress and explained he was having the stone replaced with a black diamond

The couple split up last month after a whirlwind romance, with Kat Von D proclaiming it was a 'no-brainer' to end her relationship with DJ Deadmau5.

But the celebrity tattoo artist very proudly accepted her boyfriend's proposal after he asked her to marry him on Twitter.

'I can't wait for Christmas so.... Katherine Von Drachenberg, will you marry me?' the 31-year-old DJ wrote.

The happy couple: Kat Von D and Deadmau5 pictured in Las Vegas on September 22, shortly after going public with their romance

Deadmau5, real name Joel Thomas Zimmerman, also posted a picture of the ring, a diamond flanked by two skulls which is being customised for his bride-to-be.

'Changing the diamond to a black diamond FYI. Sorry for the jpg... they'll finish the actual ring soon I hope. I love u,' he wrote.

Kat, 30, promptly tweeted in response: 'Mi corazon! Thank you all for the lovely congratulations! Please excuse me while I go squeeze the hell out of my fiance!'

#Willyoumarryme? Deadmau5 proposed to the celebrity tattoo artist on Twitter on Saturday night

Non-traditional: The DJ waited for his bride-to-be to say yes - in less than 140 characters

Deadmau5 soon logged back on to tweet about his excitement.

'Holy f****** s***. I'm engaged and stuff! Thanks for the well wishes and support from the horde and everyone else! Brb while i spend the rest of my evening with my future wife.'

The couple were first spotted out together in September after meeting at a party earlier and immediately announced their relationship to the world via social media sites.

Deadmau5 tweeted: ‘Yeah, im love... inb4 I find a f*** to give over the Internet implodes over it ;) at least I'm happy! Lol.’

Meanwhile Kat declared her love for the music producer by giving him a star tattoo below his eye to match her own.

Thank you! Kat thanked her fans for congratulating her on the engagement

It's really happening: Deadmau5 logged back on to express his excitement

She also used Twitter to announce their split, and lambaste her ex, in a series of tweets last month. 

'Man, I sure was wrong. But at least he made it a no-brainer to break that off. Lesson Learned,' she wrote.

'Clarification: Deadmau5 and I are no longer together.'

The electro-house DJ took full responsibility for the break up on his Facebook page.

'Going to spend a little while screwing my head back on,' he wrote. 'I guess I'm not cut out for relationships right now. and that's all i really want to dwell on it right now. ill figure it out. no hard feelings.'

No more trouble in paradise: Kat Von D and Deadmau5 were shopping in West Hollywood on Thursday - a few weeks after she announced their split on Twitter

But just five days later the tattoo artist was spotted beaming, kissing and hand-in-hand with her 'ex' boyfriend as they bought a new iPhone in Los Angeles.

Kat was previously engaged to Sandra Bullock's cheating ex-husband Jesse James. 

The pair ended their relationship in July 2011.

Prior to her relationship with James, she dated Mötley Crüe bassist Nikki Sixx.