Mercury and its compounds are on the Community Right-To-Know List.

OSHA PEL: CL 0.1 mg(Hg)/m³ (skin)
ACGIH TLV: TWA 0.1 mg(Hg)/m³ (skin); BEI: 35 µg/g creatinine total inorganic mercury in urine preshift; 15 µg/g creatinine total inorganic mercury in blood at end of shift at end of workweek.
NIOSH REL: (Mercury, Aryl and Inorganic) CL 0.1 mg/m³ (skin)

The Mercury(II) sulfide, with the CAS registry number 1344-48-5, is also known as Mercury monosulfide. It belongs to the product category of Inorganics. Its EINECS number is 215-696-3. This chemical's molecular formula is HgS and molecular weight is 232.65. What's more, its systematic name is mercury sulfide. It should be sealed and stored in a cool and dry place. Moreover, it should be protected from oxides, light and moisture. It is used as a red pigment when it is known as vermilion. Vermilion is known to darken and this has been ascribed to conversion from red α-HgS to black β-HgS. Natural mercury sulfide is a main raw material to manufacturing mercury. It is also used in the areas of color wax sealing, plastic, rubber and medicine and antiseptic.

Preparation: first heating and melting sulfur, and then according to the proportion adding mercury and a little of water and stirring, then the product turns into black particles, and then calcined at 600 °C. Through sublimation and sublimation cooling, mercury sulfide product is obtained.

Hg + S → HgS

When you are using this chemical, please be cautious about it as the following:
This chemical is toxic by inhalation, in contact with skin and if swallowed. It is very toxic to aquatic organisms as it may cause long-term adverse effects in the aquatic environment. It is irritating to eyes and has a danger of cumulative effects. In case of contact with eyes, you should rinse immediately with plenty of water and seek medical advice. When using it, you need wear suitable protective clothing, gloves and eye/face protection. In case of accident or if you feel unwell, you must seek medical advice immediately (show the label where possible). This material and its container must be disposed of as hazardous waste. You should avoid releasing it to the environment just refering to special instructions/safety data sheet.

You can still convert the following datas into molecular structure:
(1)SMILES: [S-2].[Hg+2]
(2)Std. InChI: InChI=1S/Hg.S/q+2;-2
(3)Std. InChIKey: LGZXYFMMLRYXLK-UHFFFAOYSA-N