Usually when Dallas dips into a river on the hunt for lost treasures, he finds predictable items like sunglasses and jewelry.

So the star of YouTube channel Man + River couldn't help but get excited when he stumbled upon an iPhone X while exploring Arizona's Salt River.

But Dallas was even more shocked when he realized that the iPhone still worked - and made it his mission to return the phone to its owner.  

Since the iPhone was not in a waterproof case, Dallas let it dry out for three days, immersing it in a tub of silicone beads and even using a hair dryer. 

While the iPhone X is advertised as 'splash, water, and dust resistant' it is not waterproof and is not guaranteed - or covered under warranty - by Apple.  

But Dallas was in luck. When he put the phone on a charger, it began to light up.

Dallas then took the phone's SIM card and stuck it into his own phone so he could find the original owner's phone number. 

'Some owners have a "backup phone" that they are using, but it has the same phone number,' he explained on his YouTube page. 

He sent a text to a number belonging to Alyssa King, asking if she had lost a phone recently. 

Dallas then filmed the next morning, when he received a call from Alyssa.  

'Hi, this is Dallas,' he says in the clip. 'Is this the lucky person who lost their phone?' 

'Yes, it is!' Alyssa screams excitedly. 

'We do have your phone,' Dallas tells her. 'I tried to power it on and it works perfectly.'

'It works?' Alyssa exclaims. 'That is the craziest thing ever!' 

Alyssa, who lives in Florida, then reveals that her she lost her phone more than two weeks ago while on vacation. 

'We should make a commercial for Apple, that's pretty impressive for an iPhone X,' Dallas replies. 

Alyssa then tells him that she is especially overjoyed with the news because the phone had photos from her newborn daughter's first five months.

'I had all her baby pictures on there and I did not back them up,' Alyssa tells Dallas. 'I was devastated.' 

'The fact that you found it, you completely turned my world upside down.' 

When Alyssa offers to pay for shipping, Dallas assures her that everything will be taken care of.

'This is the best part of my job,' he says. 'Finding the owners of these things and getting them back to you. I'm so glad this worked out.' 

Dallas called Alyssa's reaction the best he's ever gotten since he began hunting for lost items.  

'I had a lot of fun with this one,' he tells his viewers. 'Alyssa was so easy to work with and so appreciative to get her phone back with all her pictures.' 

Dallas, a free diver and scuba diver, has since posted the video to his YouTube channel, where it has been viewed more than 512,000 times.

Alyssa also posted about the experience on her Facebook page, revealing she had lost the phone while tubing down the river with a friend she was visiting in Arizona.  

'It was an absolute blast and the scenery was like something out of a movie,' Alyssa wrote. 

'However, some rapids sprung upon us out of nowhere and my phone (which I shouldn't have brought) went flying out of the plastic bag I had it in and sunk to the bottom of the river.' 

'Mind you, I was in a tube and trying to fight against a STRONG current so there was really no recovering my phone.' 

Alyssa said that while she doesn't usually 'let materialistic things bring me down', she was devastated when she realized the pictures on her phone weren't backed up.

So she was even more 'stunned, astounded, and absolutely blown away' when Dallas called her weeks later to reveal the good news. 

'I can't explain how happy I am,' she wrote. 'What a miracle guys.' 

'Thank you so much Dallas! Keep doing what you're doing!'