Also, cat urine forms crystals once outside of the bladder.

Thank you for sharing your cat's experience with blood in cat urine and crystals.
The crystals in cat urine are your greatest foe in the battle to get cat pee smell out of your home for good. They may be microscopic, but they’re tough. Before we go any further, though, I want to make it clear that I’m talking about crystals that form after the urine leaves the cat’s body, which cause odor on carpets, furniture and wherever else the cat has peed. Crystals can also form while the urine is still in the cat’s body. This is a sign of health problems, such as dehydration or pH imbalance. So, if your vet has told you your cat has crystals in his urine, it means kitty needs a better diet and/or veterinary care. Urine crystals on the carpet, however, are another matter.
In order to completely eliminate the smell and stain of the cat urine the crystals have to be removed from the surface they are sticking to.
Two of the more common minerals that cause these crystals are struvite and calcium oxalate. Struvite is a combination of 3 minerals; magnesium, ammonium, and phosphorous. We tend to encounter this mineral combination in young adult cats. They are usually treated with diets to decrease the pH of the urine. Crystals in the Urine in Cats | petMDCrystals in the Urine in Cats - Symptoms, Causes, Diagnosis ..What Do Crystals in Cat Urine Mean? | Pro Plan Veterinary Diets
In the beginning, crystals will cause the opening of the urethra to become blocked partially, so there still may be a trickle of urine. As the problem progresses, however, the trickle slows to a complete blockage. Sometimes the bladder ruptures. Generally, once a cat becomes totally blocked it takes three days to die and it's a horrible, painful death. They will begin crying in pain, and eventually the pain will put them into a coma. It is cruel to let a cat die that way. Diet can control the amount of crystals in a cat's urine. Cheap foods found in supermarkets are full of dyes and are high in ash. Both can cause crystals to form. Check the labels for cat foods that say "for urinary cat health." Also, mixing canned wet food with the dry food is helpful, as the fluid in it helps move the fluids through the cat's body and out, before the urine can get highly concentrated and become crystallized. Don't give them cow's milk, because it is not a natural food for cats. Wet food and lots of water will help more than anything. Sometimes the cat can be catheterized and just the insertion of the catheter will enlarge the opening and allow urine to run freely again. But if measures aren't taken to prevent crystals from forming again, he will become blocked again. If catheterization doesn't work, surgery will have to be performed, which slits the penis and allows urine to flow. This surgery can cost upwards of a thousand dollars. Most of the components of cat urine are actually pretty easy to clean up. This is why you might remove the stain and no longer smell cat pee for a while. Unfortunately, if you’re not using the right cleaner, you’re probably only removing a few of the less stubborn components. Feline urine is composted of urea, urochrome, and uric acid as well as several strains of bacteria. Urea is what makes cat pee sticky. Urochrome makes it yellow and causes staining. Those two aren’t much work to get rid of. It’s the uric acid that cause crystals in cat urine and that’s the real problem.As meat eaters, cats will be getting the proper fuel to promote urinary tract function. Calories come from 3 places: protein, fat and carbohydrates. In meat, there is protein and fat, but there are little if any carbohydrates. Therefore, while a cat needs protein and fat, they do not need carbohydrates. Carbohydrates are not metabolically necessary. These carbohydrates can impact the pH level of a cat’s urine, thereby creating an environment in which crystals can form. Dry kibble, on top of having inadequate moisture for cats, cannot be made without carbohydrates.Because cats have a stronger sense of smell than humans do, they can detect even the faintest whiff of cat urine. And that whiff is what they use to decide where the appropriate bathroom areas are in a given location. The litter box should smell slightly of cat urine because this attracts the cat to the box. Your carpets, however, should be absolutely clean. You’ll need to use a homemade or commercial cleaner that’s effective for breaking down cat urine crystals (not all are) on all areas the cat has soiled. After wetting, a cat digs not only to cover his leavings, but also to spread the smell. That means your cat may have splashed urine on walls and furniture near where he peed. Fortunately, there are easy ways to find soiled areas without sniffing around for them.