The Lexar Diamond is the premium series of CFexpress Type-B memory cards by Lexar. These cards come with some nice features like XQD backward compatibility, and VGP-400 certification but they are also one of the fastest CFexpress Type B cards out there.
Key Features:
- Capacity: Available in 128/256/512GB
- Read Speed: Up to 1900 MB/s
- Write Speed: Up to 1700 MB/s
- Sustained Speeds: 1600 MB/s
- Bus Type: PCI-Express 3.0 x2 / NVMe Protocols
Lexar Diamond Series 256GB CFexpress Type-B

The Lexar Diamond Series CFeB cards have a rated write speed of 1700MB/s, a rated read speed of 1900MB/s, and a rated sustain of 1600MB/s.
Tested Write Speed: 1621MB/s
Tested Read Speed: 1700MB/s
Tested Sustain: 1565 MB/s
Warranty: Limited Lifetime Warranty
I like that this card is XQD is backward compatible, VGP-400 is certified, and one of the fastest cards has a lifetime warranty.
Who is this card for? While many of the first-generation CFexpress Type-B cameras did not have the technology to support the fastest speeds of the CFexpress card, the latest batch of professional cameras do. Cameras like the Nikon Z9, Fujifilm X-H2s, and Panasonic GH6 can benefit from these new, faster CFexpress cards.
The Lexar Diamond Series is XQD backward compatible. Photographers who are still using older Nikon DSLRs in conjunction with their new mirrorless cameras can improve their quality of life by having one card that works with both systems.
Benchmarks
Benchmarks are taken with the AngelBird CFexpress reader for USB 20Gbps speeds. 4GB file sizes are tested for USB-C read and write speeds, and 64GB file sizes are tested for sustained speeds, which shows how well the cards perform under high heat.
Card | USB W | USB R | Sustained |
Lexar Diamond 512GB | 1700 MB/s | 1621 MB/s | 1565 MB/s |
Lexar Gold 2TB | 1525 MB/s | 1410 MB/s | 1382 MB/s |
You can compare the new Lexar cards to any other brand of cards in this list of the Best CFexpress Type B Memory Cards with included benchmarks – this also explains the camera testing methodology.
In-Camera Benchmarks
How the cards perform in the camera is more important than the USB speed.
I have benchmarked this card in most of the latest cameras, and it consistently performs well in terms of speed and consistency. It also handles Nikon’s 8k 60p NRAW, which runs at 722.5MB/s without issues.
I/O Transactions
Using the AJA System Test, we can examine the I/O transactions to determine whether the card is thermal throttling.
Write speeds stay mostly up around 1700MB/s with small periodic drops to around 1300 MB/s.

Durability:
The Lexar Diamond cards are built with rugged durability, similar to the Delkin Black cards and even the Hoodman Steel 1TB CFeB cards.
Operating Temperature: 14 to 158°F / -10 to 70°C
Warranty: Limited lifetime warranty in some regions.
Conclusion:
Photographers seeking the finest CFexpress Type B memory cards will find the Lexar Diamond CFexpress Type B cards to suit their needs. They ensure smooth operation and are perfect for photography and video recording at extremely high bitrates.
**This website contains affiliate links. We will earn a small commission on purchases made through these links. Some of the links used in these articles will direct you to Amazon. As an Amazon Associate, I earn from qualifying purchases. |
I bought the diamond 128gb card for my fuji x-H2S and it clears the buffer really fast compared to a uhs-ii card, about 3 seconds vs 25-30 with uhs-ii card, much better value with CFExpress.