If you've spent any time shopping for oud, you've probably run into a wall of grading terms that don't get explained anywhere: AB, Super, Super Plus, Sinking, King grade, muhassan. Some sellers use these words loosely, almost as marketing flourishes. We want to walk through what they actually mean, because the terms map to real, physical differences in the wood.

It Starts With Resin, Not Marketing

Agarwood (oud) forms when an Aquilaria tree responds to injury or infection by producing a dark, aromatic resin inside its wood. The amount of resin a piece of wood has soaked up, how deep it goes, and how evenly it's distributed, is what separates a basic chip from something exceptional. Every grading term below is really just a different way of describing resin density.

The Basic Tiers: AB, Super, Super Plus

These are the most common grades you'll see on raw, wild-harvested chips. AB is a solid entry point: real resin, real aroma, but lighter in density, which makes it approachable and more affordable. Super and Super Plus step up in resin content and depth of aroma. Within our own catalog, some of our Super and Super Plus chips come from the same trees, just different cuts sorted by how saturated each piece turned out to be.

Muhassan: Pressed and Saturated

Muhassan isn't a wild-harvest grade, it describes a process. Muhassan chips are pressed and saturated with resin, sometimes with resin from the same region's trees, until the wood reaches a density level that raw harvesting alone rarely produces. Our Merauke KCB and Merauke muhassan chips go through exactly this process. It's slow, and it can't be rushed. That's part of why muhassan material commands a higher price than standard grades from the same region.

Sinking Grade: A Literal Test

"Sinking" isn't a marketing term, it's a physical test. Resin is denser than water. Wood that's saturated enough will actually sink instead of float, exactly like this. Our Kalimantan Sinking Oud Chips are muhassan-pressed to the point where they clear that bar, which is a meaningfully higher density threshold than chips that just get called "sinking" because they're heavy.

King Grade: The Top of the Tier

King grade is the designation we use for the highest tier of sinking wood we carry, wood that doesn't just clear the sinking threshold but sits at the top of it. It's rare, it's limited to whatever a given harvest actually produces, and it doesn't get restocked on a predictable schedule. Pieces at this level are individually weighed and assessed rather than sold in bulk, since no two pieces are alike. When we say a batch is King grade, it means we've personally assessed that specific piece as the best of what came in.

Why We Also Use Grade A and Grade AAA

Separately from the raw-wood grading above, we use Grade A and Grade AAA to describe our finished oud oils. Grade A covers the large majority of our oud oil line, oils distilled from good, honest wood that we stand behind. Grade AAA is reserved for a small handful of oils, currently our Wild Kynam, Rare Wild Hainan, and Hainan Insect oud oils, where the source wood, the aging, and the extraction method are all a step above the rest of the catalog. We don't hand out AAA loosely. It's meant to mean something.

The Point of All This

None of these terms are meant to be a marketing layer on top of the product. They're supposed to tell you, honestly, what you're getting. If a batch's grade or origin ever isn't clear from the listing, email us at support@noblearoma.com, we're always happy to talk through what we know about a specific batch.