What Is a Polycone-Lined Cap?

A polycone-lined cap contains a tapered inner liner designed to compress around the rim and inner edge of a compatible bottle neck.

As the cap is screwed down, the liner moulds against the glass opening to help create a tighter seal.

This makes the closure especially useful for suitable liquid preparations that require secure storage and reduced risk of leakage.

The exact sealing performance will depend on:

• bottle-neck shape
• thread compatibility
• cap condition
• liquid type
• storage position
• filling level
• temperature changes

GL18 Bottle Compatibility

GL18 refers to a standard 18mm bottle-neck and thread size commonly used with small glass bottles.

This cap is designed for compatible GL18 glass bottles, including many amber and blue bottles used for aromatherapy, tinctures and ritual waters.

It may be suitable for:

• 100ml amber glass bottles
• 100ml blue glass bottles
• smaller GL18 glass bottles
• stock bottles with compatible 18mm threads

Compatibility can differ between manufacturers, so the cap should be tested with the intended bottle before regular use or transport.

Secure Storage Closure

This cap is intended for secure bottle closure rather than dispensing.

It is useful when a bottle needs to be:

• stored upright
• transported
• used as a stock bottle
• kept sealed between refills
• prepared before fitting another closure
• used for batch mixing

For spray application, replace the cap with a compatible GL18 atomiser.

For controlled drop dispensing, use a compatible dropper closure.

Ribbed Grip

The outer ribbed finish makes the cap easier to hold and turn.

This is particularly useful when:

• hands are slightly oily
• bottles are used frequently
• repeated opening and closing is required
• a firmer grip is preferred

The black polypropylene gives the cap a simple, durable and professional finish.

Suitable Uses

This GL18 cap may be used with compatible glass bottles containing suitable external-use preparations such as:

• essential oils
• diluted oil blends
• tinctures
• fragrance concentrates
• aromatherapy blends
• ritual waters
• stock solutions
• sacred sprays before atomiser fitting
• room-spray bases
• botanical preparations

Always check that the cap, liner and bottle are compatible with the chosen liquid.

For Essential Oils and Aromatherapy Blends

A polycone-lined closure is often chosen for oil-based preparations because the liner helps form a close seal around the bottle opening.

It may be useful for:

• essential-oil storage
• carrier-oil blends
• massage-oil preparations
• aromatic stock bottles
• professional treatment blends

Not every oil or solvent is compatible with every plastic or liner material.

Test compatibility before prolonged storage.

For Tinctures and Botanical Preparations

The cap may also be used on compatible glass bottles holding tinctures, extracts or other botanical liquids.

The bottle should be:

• clean
• dry
• correctly filled
• clearly labelled
• stored upright

The cap is sold as an empty closure only. The user is responsible for ensuring that the chosen preparation is suitable for the bottle, liner and storage conditions.

For Ritual Waters and Sacred Sprays

This cap may be used to seal compatible bottles holding:

• Florida Water
• Kananga Water
• Agua de Rosas
• Palo Santo Cologne
• smokeless cleansing sprays
• room mists
• aura sprays
• meditation blends

For storage or travel, the screw cap may be fitted in place of an atomiser.

When the liquid is ready to be sprayed, replace it with a compatible 18mm spray top.

Alcohol-based ritual colognes are flammable and must be kept away from heat, sparks, candles, incense and open flame.

How to Use

Check Compatibility

Confirm that the bottle has a compatible 18mm thread and suitable rim profile.

Inspect

Check the cap and liner for damage, distortion or contamination.

Fill the Bottle

Do not overfill. Leave sufficient headspace below the neck.

Attach

Place the cap squarely over the bottle neck and screw it on evenly.

Tighten

Turn until secure without overtightening.

Excessive force may damage the thread, liner or bottle neck.

Test

Store the filled bottle upright and check for leakage before transport or prolonged storage.

Care and Reuse

The cap may be reused where suitable and hygienic.

• Clean according to the previous contents.
• Allow it to dry fully before reuse.
• Inspect the liner regularly.
• Do not reuse if the liner becomes split, misshapen or contaminated.
• Avoid cross-contamination between different preparations.
• Do not expose the cap to excessive heat.
• Replace if the threads become worn or damaged.
• Store filled bottles upright.

Quick FAQs

What size bottle does this cap fit?
It is designed for compatible GL18 or 18mm threaded glass bottles.

What is the cap made from?
Black polypropylene with a polycone liner.

What does the polycone liner do?
It compresses around the bottle rim to help create a tighter seal.

Is the cap ribbed?
Yes. The ribbed outer finish improves grip.

Is the bottle included?
No. This listing is for the cap only.

Can it be used for essential oils?
Yes, where the bottle, cap and liner are compatible with the specific oil or formulation.

Can it be used for ritual colognes?
Yes, for compatible external-use liquids and bottles.

Is it leakproof?
It is designed to provide a secure seal, but performance depends on bottle compatibility, fitting, contents and storage conditions. Always test before transport.

Care and Safety

• Sold as an empty bottle closure.
• Bottle and contents are not included.
• Check bottle-thread and liner compatibility before use.
• Do not use with damaged bottles or caps.
• Do not overtighten.
• Store filled bottles upright.
• Test for leakage before transport.
• Label all filled bottles clearly.
• Keep filled bottles out of reach of children and pets.
• Not intended for food, drink or internal preparations unless suitability has been independently confirmed.
• Alcohol-based contents are flammable.
• Keep flammable contents away from heat, sparks and open flame.
• Replace the cap if the liner, thread or body becomes damaged.

Disclaimer

This black GL18 polycone-lined cap is sold as an empty closure for compatible glass bottles and external-use liquids.

The user is responsible for checking bottle-thread compatibility, liner suitability, chemical compatibility, sealing performance and storage conditions before use.

Sacred Essence cannot accept responsibility for leakage, contamination, staining, product loss, fire risk or other harm caused by unsuitable contents, incorrect fitting, damaged components, misuse or inadequate testing.