Mathieu Blanchard

Natural black star sapphire oval cabochon 7.8x10.5 mm

PSAM14281S

  • Type: Black star sapphire
  • Origin: Thailand
  • Shape: Oval cabochon
  • Stone weight: 4.80 ct
  • Color: Charcoal gray to dark brown
  • Dimensions: 7.8 x 10.5 mm
  • Quality and treatment: N/A
  • Birth month: N/A
  • Hardness: 9
  • Refractive index: 1.762 – 1.77
  • Density: 4
  • Care: Gently scrub with a soft brush and warm soapy water
  • Ultrasonic sensitivity: Generally safe
  • Steam sensitivity: Generally safe
  • Chemical sensitivity: Some acids, including borax
  • Heat sensitivity: Medium to low – May cause a color change
  • The image is for illustrative purposes only
  • Sold individually

This stone can be incorporated into a custom project, according to your preferences. We work directly with independent cutters and suppliers, using a respectful and transparent approach. Each stone is carefully chosen to ensure reliable quality, while supporting responsible practices.

Goes well with
  • Environmentally friendly packaging
  • Free delivery, carbon neutral, from $99 purchase
  • 1 in stock
  • Custom-made within 2 to 6 weeks

If the product is in stock, it is shipped quickly. If the product needs to be designed, the lead time can be up to 6 weeks before shipment. You can contact us to explore the possibilities.

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Each Mathieu Blanchard creation is the subject of absolute care, from its manufacture to its delivery into your hands.

1. Shipping and Security

To ensure maximum protection of your property, All our shipments are systematically made with a mandatory signature upon delivery.

  • Items in stock: Prepared and shipped quickly.
  • Tailor-made creations: Made in our workshops before being entrusted to the carrier.
  • No parcel will be dropped off without hand delivery against signature.

2. Shipping to Canada

  • Free shipping: Free with all orders of $99 and up. The carrier is at the discretion of the shipment.
  • Orders under $99: Shipping costs are dynamically calculated at checkout according to your postal code, with our transportation options (Canada Post, FedEx, etc.).

3. Shipping to France

  • Free shipping: Free with all orders of €199 and more. The carrier is at the discretion of the shipment.
  • Orders under €199: Shipping costs are calculated automatically when the cart is validated.

4. International Shipping & Customs

  • For destinations outside Canada and France, shipping costs are calculated at the time of payment according to the destination. The carrier is selected by us.
  • We do not charge Canadian taxes on orders shipped outside of Canada at checkout.
  • All orders shipped outside of Canada may be subject to local taxes and customs duties due upon delivery. We encourage you to check with your local authorities before placing an order for more information on applicable fees.

5. Partner carriers and flexibility

Our shipments are mainly carried out by FedEx and Canada Post.

In order to guarantee the best service according to the destinations or volumes, Other leading carriers may be used if deemed necessary (including UPS, Purolator, GLS, Canpar, etc.). The final choice of carrier is made by our team.

6. Follow-up and reception

  • As soon as your jewelry leaves the workshop, a tracking number is sent to you by email.
  • If you are absent when the carrier comes, a delivery notice will tell you what to do.


Rings

Option 1
1- Take a paper tape
2- Wrap the tape around your finger, loosely, and mark the tape with a pencil where it overlaps on itself.
3- Measure the size of the ribbon up to your mark (in mm)
4- Refer to the correspondence table here

Option 2
1- You get a plastic ring sizer here

Necklaces & chains

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FAQ

If the product is in stock, it is shipped quickly. If the product
Once designed, the lead time can be up to 6 weeks before shipment. You can
Contact us to explore the possibilities.

Yes, we offer customization options for many pieces of jewelry. To get started on your Custom Design project, visit this link .

To maintain the shine of your jewelry, we recommend cleaning it regularly with a soft cloth and storing it in a dry place when not worn. For pearl or stone jewelry, it is advisable to validate with the jeweler in charge of your project before designing, as some stones and inserts do not like water.

If for any reason you are not 100% satisfied with your purchase within 14 days of receipt, you may request to return any merchandise for an exchange or store credit (less shipping and handling). Only one product per order may be returned, and only for store credit or exchange. This policy is enforced to prevent abuse. See our full return policy for more details.

Prices displayed on our site do not include taxes. Tax will be added at checkout based on your location.

We use high quality materials such as gold, silver, precious and semi-precious stones. For each product, details about the materials are provided in the description.

Yes, you will receive a tracking number via email once your order has been shipped. You can use this number to track the status of your delivery online.

You can contact us by email at info@mathieublanchard.ca or by phone at (450) 531-7061, as well as via social networks. We are available to help you from Monday to Wednesday: 10 a.m. to 5 p.m., Thursday: 10 a.m. to 7 p.m., and Friday: 10 a.m. to 5 p.m.

Yes, it is possible to contact us to confirm the availability of this option.

Yes, we offer a resizing service for your rings. Please contact us to arrange an appointment.

Absolutely, we offer gold in several purities: 10, 14, and 18 carats. You can select the purity that suits your preferences and budget. If this option is not available online, please feel free to contact us.