# Bracelet gems, procurement and setting discussion

Checked **2026-10-11**. Design-discussion research, **not a manufacturing specification**. No stones bought, reserved or authenticated in person; no sellers contacted. Supplier statements are attributed, not warranties. `gems.json` is the machine-readable source record.

## Decision in one paragraph

Use the sourced **1.75 ct diamond envelope, 8.18 × 5.71 × 3.84 mm**, as the leading comparison, with its **5.71 mm width along the chain**, 36 stones and a nominal **0.40 mm edge-to-edge gap**: the stone section is **219.56 mm**, 3.66 mm over the approximate target. The original 0.30 mm arithmetic comparison remains below; the CAD uses 0.40 mm to leave room for protective corner metal rather than force 215.9 mm. Prefer independent, gallery-supported, four-corner protective baskets. This remains conditional on matching inventory, safe corner seats and articulation. The user explicitly authorized **labeled provisional ruby envelopes**: face-up dimensions are procurement targets and model depths are independent assumptions, **not measured ruby-fit CAD**. Actual matched ruby depths remain unknown. Neither nominal gap is an approved manufacturing clearance.

## Three real individual lab-diamond examples

All measurements below are **length × width × total depth**, not estimates from carat weight. These are three individual examples, **not a confirmed 27-diamond matched parcel**.

| Option | Sourced measurements, mm | Supplier evidence | Observed one-stone price | Availability claim |
|---|---|---|---|---|
| Quoted ~1.5 ct; actual 1.50 ct | **7.59 × 5.38 × 3.71** | [Palri listing](https://palri.shop/products/1-50-carat-emerald-lab-diamond-5), supplier says D/FL, IGI 816614831 | **JPY 107,800** | “Only 1 item left”; page says tax/shipping included and describes delivery within Japan. Export terms not verified. |
| Nominal ~1.75 ct; actual 1.75 ct | **8.18 × 5.71 × 3.84** | [Palri listing](https://palri.shop/products/1-75-carat-emerald-lab-diamond), supplier says D/FL, IGI 816615392 | **JPY 143,375** | “Only 1 item left”; same regional/fulfillment caveat. |
| Sourced ~2 ct; actual 2.00 ct | **8.74 × 5.81 × 4.05** | [The DiamondLab LOS-00007](https://www.thediamondlab.net/products/los-00007), G/VS2, IGI LG567377114 | **USD 1,501.20** | Listing displays selection control and delivery estimate; quantity not established. |

The 1.50 ct example is inside the quoted 7.3–7.8 mm length range, but **5.38 is not 5.50 mm**. The 1.75 ct example is close to, but not exactly, 8 × 5.8 mm. Keeping those actual differences is the point of the comparison.

The [supplier-hosted IGI image for the 2.00 ct stone](https://www.thediamondlab.net/cdn/shop/files/567377114_report.jpg?v=1743250591&width=1500) was inspected: it repeats **8.74 × 5.81 × 4.05 mm**, 2.00 ct, G/VS2, emerald cut, and is dated **February 14, 2023**. It also identifies medium girdle, long culet, CVD growth and possible post-growth treatment. This corroborates the retailer's transcription; it is not an independent IGI report-check authentication. The two Palri report numbers are supplier-listed; their report documents were not independently inspected. Do not treat the supplier's grading/stock statements as verified laboratory results or endorsement of the supplier.

## Rubies: matching face-up does not mean matching depth

### Calibrated sourcing candidates

The following are genuine supplier offerings. They advertise face-up sizes, not individually measured total-depth reports. Carat numbers are approximate ruby weights and cannot be substituted for diamond carat weights or depths.

| Supplier / emerald step-cut option | Advertised face-up | Total depth | Observed USD price per stone | Batch evidence |
|---|---:|---|---:|---|
| [Fire & Brilliance FAB ruby](https://fireandbrilliance.com/products/emerald-chatham-lab-grown-ruby-gems) | 7.5 × 5.5 mm, ~1.65 ct | **Not published** | **655 regular** | Variant available flag; inventory is untracked, not nine confirmed stones. |
| Same | 8 × 6 mm, ~2.10 ct | **Not published** | **815 regular** | Same limitation. |
| Same | 9 × 7 mm, ~3.00 ct | **Not published** | **1,220 regular** | Same limitation. |
| [deBebians](https://debebians.com/products/emerald-cut-lab-created-ruby) | 7 × 5 mm, ~1.20 ct | **Not published** | **180** | Available variant; 3–5-business-day shipping claim, not matched-nine confirmation. |
| Same | 8 × 6 mm, ~2.00 ct | **Not published** | **252** | Same limitation. |
| Same | 9 × 7 mm, ~2.50 ct | **Not published** | **348** | Same limitation. |
| [Geolite 25357s](https://geolite.com/ruby.htm) | 7 × 5 mm, average1.27 ct | **Not published** | **41.91** | Four advertised; quantity note last updated September2025. |
| [Geolite 25358](https://geolite.com/ruby.htm) | 8 × 6 mm, average2.01 ct | **Not published** | **66.33** | Two advertised; not nine. |
| [Geolite 25359s](https://geolite.com/ruby.htm) | 9 × 7 mm, average2.87 ct | **Not published** | **94.71** | Three advertised; not nine. |

Prices are size-specific values from the public [deBebians variant data](https://debebians.com/products/emerald-cut-lab-created-ruby.js) and [F&B variant data](https://fireandbrilliance.com/products/emerald-chatham-lab-grown-ruby-gems.js), not the default smallest-size page price. F&B displayed a loose-stone checkout promotion; checkout was not exercised, so it is not used as an assured price. F&B's current title/vendor is **FAB** although its old URL/image text says Chatham; confirm current maker/growth method rather than assuming Chatham provenance. Geolite's adjacent **radiant** stock is not interchangeable with the requested emerald step cut.

None of these calibrated faces exactly equals **7.59 × 5.38**, **8.18 × 5.71**, or **8.74 × 5.81**. A 7.5 × 5.5 ruby is 0.09 mm shorter and 0.12 mm wider than the selected small diamond. An 8 × 6 ruby is 0.18 mm shorter and 0.29 mm wider than the 1.75 ct example. A 9 × 7 ruby is 0.26 mm longer and 1.19 mm wider than the 2 ct example. Those mismatches cannot be hidden by scaling the model.

### Actual individual ruby L/W/D evidence — but not a usable match

[DJEVA / House of Sylas SQO627](https://djeva.com/products/star-wars-pink-laser-ruby-emerald-cut-6-11-carats) lists an individual **6.11 ct emerald-cut Czochralski ruby at 10.82 × 7.68 × 6.34 mm**, **USD560**, described as neon pink laser ruby. Its embedded variant reports **`available:false`**, despite generic in-stock/backorder text on the same page: treat it as **unavailable**. This is genuine independent ruby total-depth evidence, but it is **too large, pink rather than the requested matched red, and not available matched stock**. Its 6.34 mm depth must not be scaled down or copied into our matched-faceup target as if measured.

Near-size searches also inspected [Esslinger's emerald lab ruby](https://www.esslinger.com/emerald-cut-lab-created-ruby/) (face-up sizes only; conflicting generic sold-out/in-stock rendering), [Do Amore](https://www.doamore.com/gemstones/lab-created-rubies/emerald-lab-created-ruby/) (hand-selected-after-order, no published total depth), and [Eden Garden's 8 × 6 mm,1.9 ct ruby](https://edengardenjewelry.com/products/ruby-red-color-lab-created-emerald-cut-8x6mm-1-9ct) (EUR184.95, no depth, **not sold loose**). The [MoissaniteCo8×6 listing](https://www.moissaniteco.com/moissanite/ruby-emerald-8x6/emerald-cut-8x6mm-cultured-ruby-loose-stone) and an oversized eBay candidate returned access restrictions; no unobserved data are claimed and no restrictions were bypassed. These checks did **not** establish measured9-stone total-depth inventory near the chosen sizes.

### Defensible procurement route and independent depth information

[Precision Gem's commissioned lab-created stone page](https://www.precisiongem.com/LabCreatedGems/LabPrecisionGems.html) offers emerald cutting and ruby material. It specifies **pavilion depth P = W × 0.549**, explicitly **girdle to culet**. Therefore:

| Face-up width target | Cutter-design pavilion only P |
|---:|---:|
| 5.38 mm | 2.95362 mm |
| 5.71 mm | 3.13479 mm |
| 5.81 mm | 3.18969 mm |

These are calculations from a cutter's design, **not total depth, actual measurements, or a nine-stone order confirmation**. Crown height and girdle thickness remain required. Its calibrated option specifies **±0.18 mm** and a **USD15 adder**, which is not automatically tight enough for the final bracelet. At a worst-case common along-chain error, nine rubies at±0.18mm change the stone sum by±1.62mm. Setter-agreed tolerances and actual stone maps are needed.

Ask Elena to obtain **27 diamonds and9 red lab rubies matched by measured face-up silhouette**, step pattern, color/tone and acceptable tolerances. Obtain **each ruby's L/W/total depth separately**, plus girdle thickness, clipped-corner geometry, crown/pavilion profile and treatment/growth disclosure. Cut or select rubies to approved targets rather than infer ruby height from diamond carat weight. Confirm actual blank/yield feasibility before promising a recut of any calibrated candidate; oversize alone does not prove a feasible recut.

The JSON deliberately keeps ruby **`depth_mm:null`**. Its ruby L/W fields are explicitly **custom procurement targets**, not actual stone measurements. Provisional CAD may supply a separate `modeled_depth_mm` and visible assumption label, as the user requested. There is no evidence-supported narrow total-depth range for matching rubies here; any depth sensitivity range is a **design envelope assumption**, not supplier inventory evidence.

## Stone-section arithmetic and orientation

Fixed pattern: **[diamond,diamond,diamond,ruby] ×9 =27 diamonds +9 rubies =36 stones**. Laid-out equal-faceup stone section:

`S = 36d + 35g`, where `d` is the stone dimension along the chain and `g` is the straight stone-edge gap. No extra36th gap is added: the clasp closes the ends separately. These are stone-only quantities, **not metal extent, hinge-path length, closed bracelet circumference or skin-facing wearing perimeter**.

| Example | Width along chain:0.2 /0.3 /0.4mm gap | Length along chain:0.2 /0.3 /0.4mm gap |
|---|---|---|
| 1.50 ct,7.59×5.38 | **200.68 /204.18 /207.68mm** | **280.24 /283.74 /287.24mm** |
| 1.75 ct,8.18×5.71 | **212.56 /216.06 /219.56mm** | **301.48 /304.98 /308.48mm** |
| 2.00 ct,8.74×5.81 | **216.16 /219.66 /223.16mm** | **321.64 /325.14 /328.64mm** |

The calculation assumes all9 ruby faceups eventually match the selected diamond envelope. With actual mismatched calibrated rubies use **`S =27d_diamond +9d_ruby +35g`**, not36 times the diamond width. For example the1.75ct diamond plus8×6 calibrated rubies at0.30gap gives **218.67mm**, not216.06mm.

For comparison, the original **5.5mm quoted width** yields **205.0 /208.5 /212.0mm** at those three gaps; **5.8mm** yields **215.8 /219.3 /222.8mm**. Thus even the quoted small width does not naturally create215.9mm at0.2–0.4mm gaps.

To force 215.9 mm using the real matched-faceup examples would require width-axis gaps of **0.634857**, **0.295429**, or **0.192571 mm**, respectively. These are diagnostic arithmetic, **not recommended settings**. The final CAD retains **0.40 mm** and reports **219.56 mm** for the 1.75 ct comparison. The 2 ct example at 0.20 mm is also close at 216.16 mm, but narrower gaps may conflict with protective metal and bend clearance; proximity to the target is not evidence of safety. Length-along-chain orientation is far too long for 215.9 mm with 36 stones and positive gaps.

The user guesses the wrist is **8in or slightly less (203.2mm estimated upper reference)**, without width or front-to-back thickness. **Do not equate215.9mm stone section with wrist size or call the model personalized fit.** A clasp adds length on one reference path while basket depth changes the inner path; the difference216.06−203.2=12.86mm is **not** established wearing ease. Measure the wrist and use an illustrative—not anatomical/personal-fit—oval until then.

## Cost comparison: evidence, not a cheap2ct assumption

Single-listed-price arithmetic for27 diamonds is **JPY2,910,600**, **JPY3,871,125**, and **USD40,532.40**. These are **not batch quotes** and exclude the unresolved ruby parcel, matching labor, settings, clasp, applicable shipping/import/tax adjustments, spares and manufacture. The two same-seller D/FL examples have a higher1.75ct price; the2ct G/VS2 example is from another seller in another currency. That is not a controlled comparison and cannot establish that2ct is cheaper or dearer for the completed matched bracelet. No currency conversion has been silently applied.

For nine calibrated rubies, simple posted-price arithmetic is **USD2,268 for deBebians8×6** versus **USD7,335 regular for FAB8×6**, or **USD5,895 for FAB7.5×5.5**. Neither number guarantees nine matching physical stones, a depth range, matching color, identical growth method, or a wholesale quote. The much lower Geolite8×6 price only accompanies **two** advertised stones and an old stock-update note; nine times that price is not an obtainable parcel.

Precision Gem states a minimum **USD190–220 per stone depending material**, lists premium Czochralski ruby **USD125/ct**, and explicitly says matched pairs cost more because of extra labor/material loss. Its page does **not** quote this nine-ruby parcel. This is direct evidence that calibration/matching affects cost, not evidence of a particular premium or guaranteed lead time for9. Obtain written quotes for all three dimension targets under the **same diamond grade, ruby color/growth/cut/tolerance and parcel requirements** before ranking total procurement cost. No standard/calibrated27-diamond parcel matching these dimensions was confirmed.

## Setting comparison and Pt950/Ru review

Primary technical references: [GIA's setting guide](https://4cs.gia.edu/en-us/blog/guide-to-ring-settings/), [Stuller's bench guide](https://www.stuller.com/benchjeweler/resources/bencharticles/view/a-jeweler-s-guide-to-common-jewelry-settings), [GIA platinum V-prong benchmarks](https://www.gia.edu/quality-assurance-benchmark/setting-a-princess-cut-center-stone-in-a-platinum-mounting-with-v-prongs), and [GIA emerald-cut description](https://4cs.gia.edu/en-us/blog/diamond-emerald-cut-engagement-ring/). GIA describes emerald cuts as rectangular with **beveled corners**; do not blindly apply a pointed princess V-prong seat. The following bracelet-specific implications are **[INFERENCE]** from those construction principles, not certified dimensions.

| Setting | Protection / appearance | Low profile / metal / gap / articulation implications |
|---|---|---|
| **Independent four-corner protective baskets** | GIA says horizontal gallery supports stabilize basket prongs; Stuller calls for regular prong checks. Seats/heads should cover the actual clipped corners rather than place concentrated force on them. Open faceup, less visible perimeter metal than full bezels. | **[INFERENCE]** Good starting compromise: one rigid basket per stone and separate hinges keep retention independent of adjacent stone movement. Pavilion clearance and deeper rubies bound the attainable height; “low” cannot erase depth. Locate corner metal and hinge sweep in3D—0.30mm gem gap is not0.30mm metal clearance. |
| **Full bezel** | GIA states full-perimeter edge protection and smoother, less snag-prone borders; more of the edge covered. | **[INFERENCE]** Strong protection-led alternative, but more visible perimeter metal and larger setting footprint. Adjacent bezel walls plus bend clearance must physically fit the gap; do not promise the same tight pitch with unmodeled walls. Independent hinged bezel units can articulate, but total depth still limits profile. No metal-weight premium calculated without CAD. |
| **Half bezel** | GIA/Stuller define partial girdle coverage, leaving sections exposed. | **[INFERENCE]** Possible visual compromise only if the selected segments actually protect all four vulnerable corners. Two bars on the wrong pair of sides do not inherently do so. Requires a specific corner/seat model and separate articulating links, not a generic “safer than prongs” claim. |
| **Shared prong** | Stuller explicitly defines two stones sharing one prong to reduce visible metal. | **[INFERENCE]** Attractive continuous line, but sharing a retainer across independently moving links couples their retention and can load adjacent girdles. Not the initial recommendation for this mixed-depth articulated bracelet. A legitimate implementation needs engineered rigid multi-stone units/retention and a distinct hinge plan; do not connect moving links by the stone-holding prong. |
| **Bar setting** | GIA describes bars retaining stones with open sides, more exposed than channels; Stuller warns inconsistent seats/spacing can let stones shift. | **[INFERENCE]** Architectural look but bars consume between-stone space and may leave corners exposed unless wrapped/protected. A long rigid channel/bar strip is not an articulated tennis bracelet. Separate bar-retained units need independent hinge geometry and proof of corner/girdle clearance. |

**Pt950/Ru is a reasonable proposal, not blanket approval.** [TechForm](https://techformcasting.com/platinum-alloys/) describes950PtRu as130HV, malleable for setting and suitable for daily wear, but specifically warns of increased casting-porosity tendency and recommends its HIP process.130HV is a supplier material value, **not a fatigue strength, spring specification, minimum prong size or hinge wear qualification**. Confirm the caster's exact alloy/composition, fabrication/casting route, porosity control, finishing loss and repair method with Elena. A clasp spring or hinge pin must be independently specified, not assumed satisfactory merely because the basket alloy is Pt950/Ru.

[TechForm's dimensional-tolerance guidance](https://techformcasting.com/dimensional-tolerances-of-platinum-casting/) says shrinkage depends on alloy, wall thickness and geometry; it recommends a prototype in the actual production workflow and measuring the result. Do not invent one universal shrink compensation or clearance. Setter review must cover individual bearing cuts, remaining prong section after seats/finishing, rounded snag-free tips, corner relief/contact, culet-to-basket/wrist clearance, maximum joint angle, adjoining gem/metal collision, hinge/pin play and assembly access. GIA's V-prong page illustrates that a covered corner can still chip if the seat is wrong and expressly warns that one benchmark does not fit every design. Its princess examples are useful failure-mode guidance, not numeric dimensions for this emerald-cut bracelet.

## Short questions for Elena

1. Can we first measure snug circumference, wrist width and front-to-back thickness, then agree wearing ease and clasp contribution? The current8in figure is a guess.
2. Can you quote **27 diamonds +9 red lab rubies** for each face-up target, with actual per-stone **L/W/D**, girdle/corner measurements, color/cut matching and available quantities?
3. Would you prefer independent corner-covering baskets or protective bezels for this wear pattern, and will you approve **Pt950/Ru** plus the caster's process?
4. What finished prong/seat sections, gem/metal gaps, hinge travel stops and underside clearance do you require? Is the modeled **0.40 mm gem gap** sufficient after tolerances and articulation?
5. Shall we retain the naturally computed **219.56 mm** stone section or revise targets after the actual stone parcel, wrist and clasp are measured? No forced spacing or scaled stones.