Aurora Tennyo® is the highest grade Pearl Science Laboratory (PSL) gives to white Akoya pearls. A strand must first qualify as Aurora Hanadama®. Then PSL selects again, judging only luster and color. Few strands pass both rounds.
Want the full grading details? Read our Hanadama & Tennyo guide.
From Akoya to Tennyo in three steps
Think of Tennyo as the top of a narrowing funnel. Every strand starts as white Akoya. A small share earns Aurora Hanadama®. A smaller share of those earns Aurora Tennyo®.
- Step 1White AkoyaThe full harvest, judged on surface, flaws, luster, shape and nacre.
- Step 2Aurora Hanadama®Passes all five of PSL’s published criteria.
- Step 3Aurora Tennyo®Hanadama strands selected again for luster and color alone.
Step 2: earning Aurora Hanadama®
Hanadama (花珠, “flower pearl”) is a traditional Japanese trade term for the finest white Akoya of a harvest. For most of its history it had no fixed definition, and several labs still certify their own version. PSL published the first standardized pearl grading system in 2000. Its version, Aurora Hanadama®, requires all five of these:
| Factor | Requirement | In plain terms |
|---|---|---|
| Size | 6.0 mm and up | Large enough for the grade |
| Nacre | At least 0.4 mm thick | A thick pearl layer that lasts and glows |
| Shape | PSL “Round series” | Round, not near-round |
| Surface | Flaws rated “minimal” (微) | A very clean surface |
| Luster (teri) | Top of PSL’s scale | Weighted most of all |
How PSL applies each factor is covered in the guide: Aurora Hanadama® grading criteria.
Step 3: what teri looks like
Teri (テリ) is the Japanese word for a pearl’s glow. A pearl is built from thousands of thin, translucent layers of nacre. Light bouncing between those layers creates color, the same effect you see in a soap bubble or a morpho butterfly wing. Pearls are unusual because the color comes from light passing through the layers as well as light reflecting off them. That is why a fine pearl seems to glow from inside.
For Tennyo, PSL measures this color play with instruments rather than judging by eye. A strand must:
- reach at least 90% of the highest brightness value PSL records, and
- show three or more colors, from red through green, in its Aurora Effect pattern.
The Aurora Effect is the pattern of color that appears on the lower half of a pearl set on soft white light. PSL founder Hiroshi Komatsu described it in 2001.
TennyoAurora Tennyo® strands from our inventory. Watch for pink and green moving across each pearl as the strand turns. That color is teri.
Rare collectibleA Tennyo strand at 10.5–11.3 mmTennyo above 10 mm almost never happens. Here is one of fewer than ten strands believed to exist, with video and its PSL report.
How PSL tests a strand
- MagnificationChecks the surface for spots and blemishes.
- Optical fiberMeasures nacre thickness at points around the pearl.
- Soft X-rayConfirms nacre thickness without harming the pearl.
- Teri value analysisScores luster and color play with instruments.
- Aurora Effect photoRecords the strand’s color pattern on soft white light.
Reading a Tennyo certificate
Tennyo strands receive PSL’s SP-type certificate, a format used only for this grade. PSL’s own sample below marks the three things that set it apart:
- No. 1Teri Value Analysis is listed first on the analysis list. The method is explained on the back of the report.
- No. 2Hologram mark and Aurora Effect photo. A real photo of the strand’s aurora pattern is attached with a hologram mark, certifying the color analysis result. No two pearls share a color pattern, so the photo works like a fingerprint that ties the strand to its report.
- No. 3Highest Quality mark. Tennyo is a subset of Aurora Hanadama®, so it carries the same top mark.
PSL issues certificates only at the request of pearl dealers, not directly to consumers.
Aurora Hanadama® and Aurora Tennyo® side by side
| Aurora Hanadama® | Aurora Tennyo® | |
|---|---|---|
| Pearl type | White Akoya | White Akoya |
| Must pass | All five PSL criteria | All five, plus a second selection for luster and color |
| Judged most on | Luster, then nacre, shape and surface | Luster and color only |
| Teri requirement | Top of PSL’s scale | 90%+ brightness and 3+ colors |
| Certificate | SS type | SP type (Tennyo only) |
| Quality mark | Highest Quality | Highest Quality |
Frequently asked questions
Yes. Tennyo is selected from strands that already meet PSL’s Aurora Hanadama® criteria, which is why its certificate carries the same Highest Quality mark.
Side by side, Tennyo usually shows sharper reflections and stronger pink and green color play. The certificate is what confirms it, because PSL measures teri with instruments.
No. PSL issues certificates only at a dealer’s request, so the report comes with the strand from the supplier.
Keep reading
Cone diagram, quality pyramid, quality marks, hemisphere photos and sample certificate courtesy of Pearl Science Laboratory of Japan (sinjuken.co.jp).